Factsheet 01/09 Horticultural Bradbourne House Development East Malling Black and hybrid berries Company Kent ME19 6DZ T: 01732 848383 F: 01732 848498 E: [email protected]

Cane management and training of field grown blackberries and hybrid berries Janet Allen, ADAS (UK) Ltd

This factsheet outlines the importance of good cane management and training of field grown main season black and hybrid berries. It offers growers information on how best to achieve this, thereby reducing picking costs, reducing the incidence of disease and maximising yields.

Introduction or for further processing. Interest Poor primocane (current season’s in blackberry production for direct non-fruiting cane) and floricane The demand for well-managed sales has also experienced a revival. (fruiting cane) management of black blackberry crops (Figure 1) has risen In contrast, the area devoted to and hybrid berries can result in substantially in recent years, the production of hybrid berries high levels of cane disease, ineffec- resulting from increased popularity such as Tayberry, Loganberry and tive pest control and a substantial of fresh fruit with consumers Tummelberry remains very small. loss of yield and fruit quality. It and retailers. There has also been These crops are currently produced can also lead to significantly higher a modest resurgence in the market primarily for PYO, farm shop sales harvesting costs, at a time when for frozen blackberries, either as a and Farmers Markets, with small pay rates are rising and labour avail- constituent of mixed soft fruit packs quantities used for jam production. ability is diminishing.

1 The increased demand for fresh blackberries has resulted in an increase in the planted area in the UK

Contents

Introduction 1 Figure 7 Cane tipping can substantially increase the production of new canes Figure 1 The increased demand for fresh per plant 10 blackberries has resulted in an increase in Diagram 9 10 the planted area in the UK 1 Trailing blackberries and hybrid berries 11 Figure 8 The double wire trellis system The cost of poor cane management 3 separates floricane from primocane, which can improve presentation of fruit to pickers 11 Figure 2 Primocanes that are allowed Diagrams 10 & 11 11 to trail on the soil surface are more difficult Figure 9 Closely spaced plants trained by to lift and tie in 3 weaving across the support wires 12 Figure 10 Well managed plantation of ‘Silvan’ The approach to cane management 3 on a vertical wall trellis. Primocanes are held upright using two pairs of mobile wires 12 Methods of removing and controlling primocane 4 Optimum specification for the support trellis 13

F igure 3 Chemical desiccants have been Vertical wall support trellis 13 used successfully for many years to control Posts 13 unwanted primocane – photographed in Wires 13 raspberry crop 4 Brace 13 Table 1 Summary of terms of SOLA for use Plant spacing 13 of Shark in blackberry and rubus hyprids 4 Diagram 12 13 Fruiting lateral supports 14 Crop establishment and early management 5 Double Wire support trellis 14 Diagram 13 14 Choice of planting material and subsequent cane management 5 Securing canes to support wires 15 Weaned ex micro-propagated plants 5 9 cm pot plants 5 Figure 11 Typical plastic clips used to 2 year old plants 5 secure canes to wires 15 Once or twice-fruited 5–10 litre containerised plants 5 Old fruiting cane removal and clearance 15 Table 2 Guide to the growth habit of commonly grown blackberries and Labour requirement 15 hybrid berries 5 Early support 6 Biennial cropping 16 Figure 4 Primocane should be trained upwards, spaced out across the support trellis 6 How does it work? 16 Diagram 1 6 Figure 12 Biennial crop of ‘Silvan’ in the fruiting phase 16 Cane management and training from year Figure 13 Biennial crop of ‘Silvan’ in the two onwards 7 vegetative phase 16

Erect and semi-erect blackberries 7 Cane tipping and management in closely spaced plantations 7 Figure 5 Many growers cut back primocane to encourage the production of branching 7 Diagram 2 7 Figure 6 Primocanes can be held in position by a pair of wires. Note the tape used to fasten canes to wire 8 Diagrams 3, 4 & 5 8 Diagrams 6, 7 & 8 9 Cane tipping and management in wider spaced plantations 10 The cost of poor summer will have rooted at their tip, or leaf petioles tend to be less easy to and are more difficult to lift and tie handle than spine-free varieties. They cane management in (Figure 2). take longer to pick and it is essen- Varieties which bear spines on their tial that they are managed correctly to The current commercial cost of floricane, primocane, fruiting laterals reduce costs to a minimum. picking blackberries in a well-man- aged plantation, where fruit is displayed well to pickers, is typically £1,200 per tonne. Where cane management is poor, access to fruit is hampered, which leads to reduced picking speeds and increased costs. For a 15 tonne/ha crop, the increase in picking costs could be as much as 33%, rising from £18,000 to £24,000 per ha. Poor cane management during spring, summer and autumn can also lead to a marked increase in the time and cost incurred for winter pruning. This is especially so where cutting out and tying in is left until the winter. By this time, in trailing varieties, many of the primocanes which have been allowed to trail on the soil surface all 2 Primocanes that are allowed to trail on the soil surface are more difficult to lift and tie in

The approach to The following growing season, water and nutrients, leading to re- primocane becomes floricane, pro- duced berry number and size cane management ducing flowers during the spring (yields). They will also compete with and summer and fruit from early themselves, limiting growth and cane Main season blackberry and hybrid summer into the late autumn months quality, producing an adverse effect berries bear their fruit from mid to (depending on the variety). on yields in the following season. late summer into the autumn months. All established plantations, (un- Excessive numbers of primocane, During their growing season, the less managed biennially), have particularly those emerging between rows of established plantations con- both primocane and floricane present plants in the crop rows will reduce tain both primocane (spawn) and in the crop rows throughout the access for pickers and reduce spray floricane (fruiting canes). The spring, summer and autumn months. penetration for pest and disease primocane emerges from the soil in After the fruiting season the floricane control. It is therefore necessary the spring from buds at or just should be cut through at ground with some varieties in some years to below the soil surface around and level, removed from the crop row and reduce primocane numbers during between the bases of each plant. disposed of either by pulverising in the spring and summer months. The primocane grows through the the alleyways or by removal from the In the case of erect and semi-erect spring, summer and autumn, reaching plantation for burning or other growing blackberries, primocane may 1.5–3 m or more in length. means of disposal. At the same time, need to be cut back (tipped). This Primocanes can either produce the stand of primocane should be will encourage branching, improve a single stem or be branched. Their reduced in number selecting cane habit so that it remains upright growing habit varies by variety and the required diameter and length of during its growing season and lead can fall into one of these categories: cane to crop the following year. to the production of the required All unwanted primocane should be number of canes of a suitable stature 1 Erect – those that grow upright. cut out at ground level, removed from and thickness for cropping the the crop rows and disposed of in the following year. Be aware that despite 2 Semi-erect – those that grow same manner as the spent floricane. the removal of unwanted primocane upright initially and then become Growers should aim to retain during the spring and summer trailing. sufficient primocane to provide a months, some further cutting out similar or improved crop the following of unwanted or damaged canes may 3 Trailing – those that naturally year. However, it should be noted still be necessary at the end of the grow or trail along the soil surface that the emergence of excessive growing season. throughout their growing period. numbers of primocane in spring can have a detrimental effect. They will compete with floricane for light,

3 Methods of removing and hybrid berries, such damage exercised to avoid contacting those provides infection sites for crown gall canes to be retained. and controlling (Agrobacterium spp.) or cane blight To destroy primocane around (Leptosphaeria coniothyrium). fruiting plants in biennially-cropped primocane An alternative to mechanical plantations and to completely control is the use of a chemical remove the first flush of primocane Primocane removal in blackberry herbicide or desiccant directed care- in close-planted annually-cropped and hybrid berry plantations is fully with a shielded sprayer onto plantations, Shark can be applied generally carried out by hand, using primocanes growing in the alleys throughout the base of the crop row secateurs or pneumatic pruners, and between plants in the row to contact all primocanes. However, cutting through unwanted primocanes (Figure 3). Materials currently being in so doing, growers should be aware at their base. The cane is removed used include glufosinate-ammonium that the second flush of primocane from the rows and placed in the alleys, (Harvest), diquat (Reglone) and will be thinner, weaker and poten- to wilt and then be pulverised. This the desiccant carfentrazone-ethyl tially earlier cropping the following applies both to primocane which has (Shark). year. If unsure about when and emerged from around the base of Shark has a Specific Off-Label where to use Shark, be guided by an stools (individual plants) within each Approval (0551/08) for use to experienced crop agronomist. row and from the soil between plants remove unwanted primocane grow- Shark may be used under the in the rows. ing in both outdoor and protected terms of the SOLA on blackberry and Primocane emergence between raspberry, blackberry and rubus rubus hybrids as outlined in Table 1. plants in the rows does not gen- hybrids. Shark has now been used For full details of use, consult erally occur in semi-erect, spine-free by black and hybrid berry growers to the current SOLA. In practice, blackberry varieties such as Loch remove primocanes up to 20 cm in growers have found that lower rates Ness and Chester Thornless where height. Primocanes treated include of use than those given in Table 1 emergence is confined to the stools of those in alleys, outside the crop row will provide a satisfactory kill of individual plants. However, black and and between plant stools. Individual unwanted primocane in these crops, hybrid berry varieties with a trailing canes around the base of floricane provided that the cane is at no habit and spiny canes such as Silvan, and stools are sometimes treated more than the recommended height Fantasia, Kotata and Tayberry do by growers, but great care must be for treatment. have a tendency to produce spawn between stools and in the alleyway. These unwanted canes may need to be removed two or three times prior to harvest. To save time and reduce the cost of management in the spring and summer months, some growers use mowers to remove primocanes that have emerged between crop rows and hand-held strimmers between plants in the rows. Such uses however require considerable care to avoid cutting through or damaging the rind and underlying tissue of the primocane to be re- tained. This damage reduces cane vigour and winter hardiness. It can also provide egg-laying sites for female raspberry cane midge on 3 Chemical desiccants have been used successfully for many years to control unwanted loganberry and tayberry. On black primocane – here photographed in a raspberry crop

Table 1 Summary of terms of SOLA for use of Shark in blackberry and rubus hybrids

Product Active ingredient Max. individual Max. total dose Maximum Latest time of dose (litres of (litres product/ number of application product/ha) ha/crop) treatments

Shark Carfentrazone-ethyl 0.8 1.6 – 21 days before (MAPP 12762) harvest

4 Crop establishment glasshouse or polythene clad tunnel. Some growers choose to retain intact They are planted out into their fruiting floricane already present on these & early management position in either late winter or early plants, after planting, to take a small spring, by which time they will have crop of fruit in the planting year. When establishing a new plantation produced at least one cane, and a This can work well without any detri- of black or hybrid berries, the choice substantial root system. mental effect upon plant establishment of management and training sys- and primocane production, provided tem should take account of the growth 9 cm pot plants that the plants are not subjected to habit of the variety to be grown. Raised from micro-propagated any undue stress during their growing Growth habits vary enormously bet- stock or propagated from leaf bud season. Containerised plants are more ween varieties, but can generally be cuttings, these plants have been suitable for this technique. However, grouped into the three categories grown on for one season and can many growers choose to remove all described on page 3 (Erect, Semi- be planted out directly. Successful of the cane present on both container erect and Trailing). Table 2 provides a establishment requires good soil and bare-rooted plants at the time guide to which category some of the conditions, adequate supplies of of planting, to ensure that they grow commonly grown varieties fall into. irrigation and fertigation, good weed away well in their first year. In the planting year, the canes of control and a well sheltered site all cultivars often display a trailing or or protection by polythene tunnels. Once or twice-fruited 5–10 litre semi-trailing habit. In the following year Without these, growth in the plant- containerised plants the true form is more fully expressed. ing year can be very poor, so that Some growers choose pot grown However, irrespective of growth cane produced in the first year has plant material that has previously been habit, all varieties must be trained and to be cut back to ground level in the used for cropping under glass or supported by a post and wire trellis. late winter of the following year. If tunnels. They are planted in the soil This ensures the separation of the planted in the spring, whilst they are in June or July after late spring floricane from the primocane, aids the actively growing, their cane should cropping. These plants are in reality production of primocanes and posi- be kept intact. If winter-planted, the 3 or 4 years old at the time of planting tions as much floricane as possible in cane is usually cut back to just out in the open, as their primocanes front of the pickers. above the point where it has been have usually been removed at The choice of management after produced from the top (crown) of least once during the harvest imme- planting and in the establishment year the plant. diately prior to their purchase. will depend upon: Characteristically, they have a well- 2 year old plants established root system, but this can • type of plant (bare rooted, module Offered for sale either bare-rooted be pot-bound. They may have been or container raised) (in winter) or in 10 litre containers. weakened by previous treatments These are the easiest size of plants and are more likely to be affected by • date of planting to establish as they already have pest (blackberry leaf midge) or a substantial crown and root system. disease (downy mildew, rubus stunt). • soil conditions If well cared for, they can produce Successful establishment of such 3 or 4 good quality primocanes plants in the open often proves to be • availability of irrigation/fertigation in the planting year and as a result, far more difficult than envisaged. an appreciable crop the following • degree of site exposure or summer or autumn. By the third year protection (eg Spanish tunnels) after planting such plants can be fully cropping.

Choice of planting material and subsequent cane Table 2 Guide to the growth habit of commonly grown blackberries and management hybrid berries

Planting material can be purchased Growth Blackberry Hybrid berry in a range of forms and the type used will dictate the subsequent Erect Apache, Navaho, Ouchita management required. Semi-erect Chester Thornless, Helen, Loch Maree, Weaned ex micro-propagated plants Loch Ness, Loch Tay, Triple Crown These are usually unsuitable for planting out directly, but are normally Trailing Bedford Giant, Black Butte, Black Tayberry, re-potted in a soil-less compost into Diamond, Black Pearl, Fantasia, Karaka Loganberry, 9 cm and subsequently 2 litre pots. Black, Kotata, Nightfall, Obsidian, Boysenberry, They can either be grown on outdoors Metolinus, Silvan Marionberry, in a sheltered and well-drained Tummelberry container bed or alternatively in a

5 Early support Any floricane should be cut through at ground level, removed Whatever type of plant is used to and disposed of. establish a plantation, it is important The primocane should be to provide the primocane and floricane trained upwards, spaced out across (where present) with support from the support trellis and fixed securely the onset of growth or from planting to the wires at various heights to onwards. This is necessary to keep produce a fan of canes to either side the canes off of the soil surface, to of each individual plant (Figure 4). prevent wind rocking or rubbing and Alternatively, the canes can be adequately display any fruit to pickers. secured in position to one side of By the late autumn of the plant- the centre of each plant (one way ing year, plants may have just current system of training). Diagram 1 illus- season’s primocane or a mixture of trates four different training methods 4 Primocane should be trained upwards, primocane and floricane present. that can be used. spaced out across the support trellis

Diagram 1 Methods of training trailing & semi- trailing blackberries & hybrid berries

Two-way rope Young cane 2.5 mm HT top wire 0.45 m

0.45 m 2.5 mm non-HT 1 .8 m lower wires 0.45 m

0.45 m

2.0–3.0 m Fruiting cane Stool

One-way rope Fruiting cane Young cane 2.5 mm HT top wire 0.45 m

0.45 m 2.5 mm non-HT 1 .8 m lower wires 0.45 m

0.45 m

2.0–3.0 m Stool

Fan Fruiting cane Young cane 2.5 mm HT top wire 0.45 m

0.45 m 2.5 mm non-HT lower wires 1 .8 m 0.45 m

0.45 m

2.0–3.0 m Stool

Weaving Fruiting cane Young cane 2.5 mm HT top wire

0.45 m 2.5 mm non-HT 0.45 m lower wires 1 .8 m 0.45 m

0.45 m

2.0–3.0 m Stool

6 Cane management Cane tipping and management in height in June (Diagram 2a). Two in closely spaced plantations or more laterals may be produced and training from In closely spaced plantations from the stubs. The stub of the primary (0.9–1.5 m between stools in the row), cane will continue to grow for a while year two onwards where the vertical wall trellis is used to after tipping, so by the end of July support the crop (Diagram 9, pg 10), they will have reached around 30 cm During the winter, the primocane the first flush of primocane may be in height (Diagram 2b). The laterals becomes floricane and just prior to tipped back to within 15–20 cm of their will reach 1.8–2.0 m by the end of their bud break, their tips should be cut base as soon as they reach 60–90 cm growing season (Diagram 2c). back by 20–45 cm to remove any dead, diseased or weak wood. The remaining cane should be at least pencil thickness and individual bud nodes at least 15 cm apart. This removes apical dominance encouraging all lower buds to break evenly down the cane’s length, leading to the production of well- spaced fruiting laterals, which bear fruit of a good size. By May, new primocane will have started to emerge from around the base of the stool. The number of primocanes that emerge is dictated by the vigour and growth habit of the variety: 5 Many growers cut back primocane to encourage the production of branching • 2–6 primocanes – weaker growing erect and semi-erect cultivars • 6–12 primocanes – vigorous trailing Diagram 2 Training system for intensively planted erect & semi-erect cultivars blackberries

2a Primocanes begin to grow and 2b Several new shoots grow from each Erect and semi-erect are tipped at 15 cm long to en- cane stub. The best are selected and blackberries courage multiple shoots to form. trained upwards. Extension growth of original stub continues. Erect and semi-erect blackberries Primocanes tipped at 15 cm usually assume their natural New shoots growth habit in their second year. Primocanes Managing them in the same way as trailing varieties often produces Original stubs unsatisfactory results. The stout, 15 cm stiff and often very long primocane 30 cm produced by varieties such as Loch Ness and Chester Thornless are Stool Stool not easily separated from pickers or machinery. They are also prone to wind rock and breakage during 2c Growing primocanes are spaced out and clipped or laced in vertical the growing season and can be diffi- position to support wire. cult to manipulate and tie onto the support trellis. The number of Support wire Post primocanes produced in some years by these plants can also be very small, resulting in a reduced yield potential. To counteract this, many growers Primocanes cut back the primary primocane when 1.8 m it has reached 60–120 cm according to plant spacing and vigour, to encou- rage production of several branches (laterals) (Figure 5). The height of tipping and how far the canes are cut back depends on the height at which the laterals are required. 0.9–1.5 m

7 As primocanes grow, they are held upright and against the face of the support trellis, out of the way of machinery and pickers, so that the current season’s fruiting laterals grow out through them and are well presented at harvest. Primocanes can be held in position by a pair of mobile wires (Figure 6), which are held by hook nails driven into either side of each post at intervals, the first at 0.45 m above the ground. The wires are tensioned at each end with a short length of galvanised chain, located over the head of a nail or the end of a bolt fixed to the end post. As the canes grow, the wires are moved upwards to a higher position on the trellis to provide optimal support. Diagrams 3, 4 & 5 illustrate how this system works. Alternatively, the canes can be supported using several lines of string stretched out between the support posts at various heights as the cane grows, but as the string tends to stretch, tension is lost so this form of support is poorer. 6 Primocanes can be held in position by a pair of wires. Note the tape used to fasten canes to wire

Diagram 3 Vertical wall support trellis-hook nails & mobile wires

Intermediate post Intermediate post 15 mm

2.5 mm non HT mobile wires Hook nail

Hook nail 2.5 mm non HT mobile wire

Diagram 4 Method of holding chains on end posts with two nails

Plan view Side view

End post (125–150 mm) End post (125 –150 mm)

75 or 100 mm galvanised roundhead nails Nail heads protrude 30–40 mm

Minimum 0.6 m of 4 x 26 mm galvanised welded straight link chain

2.5 mm non HT mobile wires

Diagram 5 Method of holding chains on end posts with single bolt

End post (125 –150 mm) End post (125 –150 mm)

M8 coach bolt thread protrudes Single bolt at each approx 40 mm from post wire position

Minimum 0.6 m of 4 x 26 mm galvanised welded straight link chain 2.5 mm non HT mobile wires

8 A fter h arvest , t h e c urr en t season’s can e h as suffic i en t l y l i gn i fied to avo i d n ow flori can e) sh o u ld be c ut b a c k spen t flori can e sh o u ld be c ut t hr o ugh dam a ge fr om c l i ps or tw i n e . I f so, to wi t h i n 15–20 cm o f t h e top fixed a t gr o un d l evel an d r em oved fr om t h e can es sh o u ld be h eld u pri gh t a gai nst w i r e o f t h e t r el l is. Any si de sh oo t s su pport t r el l is w i r es. Th e pri m ocan es t h e t r el l is usi n g m obi l e w i r es or pr od uced d uri n g t h e pr ev i o us l a te sel ected to cr op t h e fol l ow i n g year st ri n gs w h i ch , a fter flori can e r em oval , sum m er an d a ut um n sh o u ld be ei t h er sh o u ld be pl a ced d i r ect l y i n to th ei r ar e usual l y c l i pped toge t h er usi n g com pl e tel y r em oved or sh orten ed to fru i t i n g posi t i on an d ei t h er l a ced gal van ised G-c l i ps (Di a gram 7) w i t h i n 15–20 cm o f t h ei r b ase . or c l i pped to th e top (or to p an d m i d) a t several po i n t s be tween ea ch se t W i t h t h is sy stem o f t rai n i n g , t h e w i r es o f t h e su pport t r el l is. Di a grams o f i n term ed i a te su pport post s. Th is can es sh o uld be sp a ced 10–20 cm 6 , 7 & 8 i l l ust ra te di ffer en t op t i ons for stops t h e can es fr om m ovi n g an d ap art , w i t h 5–10 can es per m e t r e o f a tta ch i n g can es to wi r es. Th is work abra d i n g ea ch o t h er i n t h e w i n d. r ow r e tai n ed to cr op per an n um . m ay be del ayed un t i l t h e en d o f t h e At t h e en d o f t h e w i n ter, j ust pri or gr ow i n g season , w h en t h e ri n d o f t h e to bud br eak , t h ese can es ( w h i ch ar e

Diagram 6 Black & hyprid berries support system-clips

These can be used as an alternative to lacing with twine

Various sizes available

Plastic clip Plastic clip

Blackberry cane Blackberry cane

Support wire Support wire

Diagram 7 G Clip to hold pairs of mobile wires together

Galvanised steel Mobile wire G clip 30 mm G clip

Diagram 8 Black & hyprid berries support system – lacing technique

1 Move from previous cane to next cane to 2 Away from wire, form loop in twine be tied-in, keeping tension on twine with one hand

Blackberry cane

Support wire

Lacing twine

3 With other hand, pass end of twine 4 Pass end of twine behind cane, 5 Position cane correctly against wire, (on spool) in front of cane and over top of wire and through loop pull knot tight and proceed to next below wire cane keeping tension on twine

9 Cane tipping and management in In both cases, it may be necessary to they reach a height of 1–1.2 m. wider spaced plantations cut back some shoot tips and laterals The cane stubs and laterals are then In wider spaced plantations (1.8–3.0 m produced by primary and secondary supported by two or three wires between stools in the row), where canes in the previous summer. running down the centre of each row. the vertical wall trellis (Diagram 9) is Some growers prefer to use the At the end of the season, the spent used to support the crop, then tipping double wire trellis to support floricane is removed as usual. should take place when primocanes semi-erect black or hybrid berries reach 60–120 cm in height. The canes (Diagrams 10 & 11). In this case, the should be pruned back to around primocanes are tipped back when 30 cm below the height at which branches are required. Each pruned cane will produce 2–4 branches (laterals) which in turn can be tipped later in the summer to induce further lateral production. By the end of the growing season, this cutting back will have substantially increased the number of canes per plant com- pared with un-tipped plants, all of which should bear fruit the following summer (Figure 7). As they grow, the primocanes may be held erect against the support trellis by lines of strings or using the mobile wire system described before for closely spaced plantations. After harvest and the removal of spent floricane, the current season’s primocanes are selected, trained and secured onto the support trellis, normally using the two-way rope training method (Diagram 1, pg 6). Where a one-way method of cane training is practiced, the primocanes are trained up and clipped into their fruiting position as they grow into the section of the trellis wires which are not occupied by floricanes (Diagram 1, pg 6). 7 Cane tipping can substantially increase the production of new canes per plant

Diagram 9 Vertical wall support trellis

2.5 mm HT top wire Intermediate post Bracing post (75–100 mm) (100–125 mm)

0.45 m Strut 0.45 m (75–100 mm) 1.8 m 0.45 m

0.45 m

End post 1.8 m (125–150 mm )

1.8 m

2.5 mm non-HT 0.6 m lower wires

6–8 m 0.9 m

6–8 m

2 – 2.5 m

10 The new primocane and laterals crop row. Alternatively, they may are then split evenly into two be gathered together around the and wound along and clipped to centre of each plant, the bunch the wires on either side of the centre of canes being secured with strings or of the row. This system separates baler twine to each of the the primocane from fruiting canes fixed wires of the support trellis as and provides a good display of fruit they grow. to pickers (Figure 8). On reaching the top wire of the trellis, the bunch is left intact and either trained along the top wire Trailing blackberries and in one direction or split in two and hybrid berries the canes trained in both directions above the floricane (Diagram 1, pg 6). With trailing varieties, the primocanes This keeps the primocane well out are usually kept intact, being allowed of the way of pickers and prevents to fall outwards and downwards damage by machinery or others work- 8 The double wire trellis system separates onto the soil surface in the alleys or ing in the plantation. After harvest, floricane from primocane, which can improve trained to run along the sides of each all of the floricanes are cut through presentation of fruit to pickers

Diagram 10 Double wire support trellis

2.5 mm HT top wire Intermediate post Bracing post (75–100 mm) (100–125 mm) Strut (75–100 mm)

1.8 m End post (125–150 mm)

0.45 m 0.6 m 0.45 m 2.5 mm 1.8 m non-HT lower wires 0.45 m

0.45 m 50x75 mm timber 6–8 m cross pieces 2–2.5 m Upper 0.6 m long 0.9 m Lower 0.9 m long 6–8 m

3.0 mm HT Wire brace

Diagram 11 Training of trailing or semi-erect black & hybrid berries on double wire support trellis

Side view Front view Plan view

Top Wire Support Pimocane fixed 0.45 m wire to wires on post 0.6 m Post Support wire Timber cross 0.45 m piece Post 1.8 m Primocane Support Top timber 0.45 m wire cross piece 0.9 m Floricane

Timber cross Floricane fixed 0.45 m piece to support

wires on top timber cross piece 0.6 m

Primocanes are tipped at about 1.2 m above ground level to Wires on bottom timber cross encourage branching. At end of growing season, these are fixed piece stop growing primocanes to support wires on top timber cross pieces from flopping into alleyways

11 at ground level, removed from the to leave a short 1 or 2 bud stub. on spacing. However, if trained support trellis and disposed of. Any dead cane tips should be pruned correctly, they can be managed suffi- This year’s primocanes are then back to healthy tissue of at least ciently well to support the primocanes detached from the top and lower pencil thickness. Dead or badly dis- adequately, whilst presenting fruit wires of the trellis and laid out on the eased canes should also be cut well to pickers. Figure 10 illustrates ground, with weak or badly damaged back to healthy tissue or completely a well managed plantation of the canes cut through at their base removed at this stage. trailing variety ‘Silvan’ on the vertical and discarded. Each remaining cane In fully established trailing black wall trellis. is carefully lifted and then attached and hybrid berries, total numbers to each of the three lower fixed wires of both primocane and floricane will of the support trellis. They can be range from 6–18 per plant depending wound onto the wires, clipped, taped or tied. In all cases, it is important to secure the canes and to fix the wires of the trellis on its upwind side, to minimise the risk of canes or wires detaching themselves during windy weather. The canes are trained to the wires in one of four ways, as illustrated in Diagram 1, pg 6. They can be trained to either side of the centre of each plant (Two-way rope – Diagram 1 and Figure 4, pg 6), to one side only (One-way rope – Diagram 1, pg 6), in a fan shape (Fan – Diagram 1, pg 6) or woven (Weaving – Diagram 1, pg 6 and Figure 9). In a one-way rope system, the primocanes can be positioned in this way as they grow during the summer and autumn. In all trailing black and hybrid berries, pruning out and tying in should be carried out as soon after harvest as practically possible. Where the first 9 Closely spaced plants trained by weaving across the support wires flush of primocane removal has taken place or primocane growth has not been adequate prior to harvest, the removal of the floricane will give the primocane an opportunity to grow away and to reach the required length and diameter by the end of its growing season. In areas where the winters are likely to be sufficiently cold to cause cane damage after pruning out, the current season’s primocane may need to be lowered from the top to the lowest or lowest two wires of the trellis, in such a way as to prevent the cane tips from rooting into the soil. Canes are left in this position through the winter and then released, re-selected, placed and secured into their fruiting position before bud break in the late winter. In all cases, some additional prun- ing will be required just prior to bud break in the spring. Side shoots that were produced by the canes in the autumn should either be cut back to 10 Well managed plantation of ‘Silvan’ on a vertical wall trellis. Primocanes are held upright using their base or alternatively pruned two pairs of mobile wires

12 Optimum Posts 3 wires spaced at 0.45 m intervals • End post 2.7 m long x 125–150 mm above it, so that the top wire is specification for the round, set 0.9 m in ground, 1.8 m just below top of the posts. Wires above are strained with radisseurs or other support trellis suitable wire strainers and all are • Bracing post 2.7 m long x 100–125 fixed to the posts with heavy duty Post and wire specifications will vary mm round, set 0.9 m in ground, galvanised staples. All wires should according to site conditions, including 1.8 m above be of 2.5 mm galvanised steel. The top soil type, degree of exposure, length wire may be high tensile (HT), the lower of row, etc. Listed below are typical • Intermediate posts 2.4 m long x wires non-HT. Use 3.0 mm HT for specifications for the vertical wall and 75–100 mm round, set 0.6 m in wire brace. double wire support trellis systems ground, 1.8 m above on average sites. Whichever support Brace trellis is used, all posts and timber • Bracing struts 75–100 mm round Various methods of bracing are should be pressure-treated to ensure employed, including simple wire brace, acceptable durability. • Intermediate posts are spaced wooden strut and wire brace and strut. 6–8 m apart in the row, depending The wire brace and strut is generally Vertical wall support trellis on site the strongest and least likely to pull the (Diagram 9, pg 10) end post out of the ground (Diagram 12 Wires and Figure 4, pg 6). This trellis can be used for erect, This trellis has three or four fixed semi-erect and trailing black and wires. The bottom wire is 0.45 m Plant spacing hybrid berries. above the ground and the other • 0.9–3.0 m apart in the row

Diagram 12 Black & hyprid berries support systems – methods of bracing end posts

Wooden Strut Wire brace & strut

End post Wire 2.5 mm HT End post Timber bracing strut 2.5 mm HT (125–150 mm) Strainer top wire (125–150 mm) (75–100 mm) top wire

2.5 mm non-HT 60° lower wire 60° 3.0 mm HT Wire brace

0.5 m Bracing post 0.9 m 0.9 m (100–125 mm) 0.9 m

Timber strut Peg (75–100 mm) (75–100 mm) 0.9 m

Simple wire brace Method of attaching timber cross piece to post

End post Wire 2.5 mm HT Post Timber cross piece (125–150 mm) Strainer top wire notched into post (nailed or bolted)

3.0 mm HT Wire brace 45°

2.5 mm non-HT 0.5 m 0.9 m lower wire

Peg (75–100 mm)

13 Fruiting lateral supports with a single galvanised nail to allow it • A further single wire fixed to post. Varieties which produce long fruiting to pivot. String or tape attached to the laterals when grown under cover require uppermost end is left in place to help • At the bottom, another set of additional support for them during support the fleece. double wires separated by a the growing season (Diagram 13). This timber cross piece 0.9 m long. is achieved by using up to 4 timber battens, each 0.6 m x 50 mm x 25 mm, Double Wire support trellis The wires are spaced at 0.45 m nailed horizontally onto each inter- (Diagrams 10 & 11, pg 11) intervals up the post, with the upper- mediate post, either just above or just most wire just below the top of the below each of the four fixed wires. This system is usually adopted for post. The cross pieces are notched During the growing season, tapes, vigorous semi-erect varieties which into the support posts and held with baler twine or similar are strung bet- produce particularly stout canes heavy duty galvanised nails. ween the ends of these timbers to eg Chester Thornless. The bottom pair of wires stops support the fruiting laterals. The tape The end and intermediate posts the growing primocanes from or twine is removed at the end of the are of similar specification to the flopping out into the alleyways. season, but the battens remain in vertical wall trellis, rising 1.8 m out As the primocanes grow, they are place. To withstand the weight of the of the ground. Likewise, the top wire clipped to the top and third wire fruiting laterals, the battens at the end is 2.5 mm HT with 2.5 mm non-HT down which are fixed directly to the of the row should be of 50 x 75 mm below. Four sets of wires are used; posts, to keep them out of the way timber, and be nailed to the outside from the top these are: of the floricane. of the end posts. A modification is to attach the top • A single wire fixed directly to post. most batten so that it can be pivoted into the vertical position and thus • A set of double wires separated provide support for fleece that may be by a 0.6 m long cross piece of used to cover the crop in the spring. 50 x 75 mm section timber nailed This top batten is fixed to the post to the post.

Diagram 13 Vertical wall support trellis – lateral supports

Top timber batten pivots to support fleece

0.6 m Top Wire Post

0.45 m Support Timber batten Top batten can be pivoted Wire (25x50 mm) into vertical position. Tape

or string left in place on one end helps support fleece Tape or string on end of battens to 0.45 m support fruiting 1.8 m laterals

0.45 m Fruiting Floricane Lateral clipped to

support wire

0.45 m

Position of battens on end post

Top Radisseur End post End battens must be stronger (50x75 mm) and Wire (25–150 mm) fixed to outside of end posts to resist weight of fruiting laterals. Top battens are fixed with single heavy duty galvanised nail to allow pivoting. Bracing strut 50x75 mm Timber end battens on outside of post

14 Securing canes to are more expensive to purchase. When securing canes to the support A cheaper alternative is plastic tape, wires, they should always be support wires which is attached using a purpose attached on the prevailing wind side. designed gun. These are quick Experience shows that they remain Whichever method is used, the aim and easy to use, but are less secure secure for longer on this side. is to secure the canes tightly to and more prone to breaking or prevent them from becoming loose. perishing during the winter months. This can lead to abrasion against the wire, which gives rise to cane break- age, disease infection and increases the risk of cold injury occurring. The three preferred systems are the ‘lacing technique’ (Diagram 8, pg 9), use of plastic clips (Diagram 6, pg 9 and Figure 11) and plastic tape gun (eg Max Tapener – Figure 6, pg 8) The lacing technique employs twine (medium grade plastic baler twine), which runs down the length of the row, securing each cane to the wire. This requires staff to be trained to perform the task well and can initially take longer (until the labour force achieves proficiency in the task). In contrast, it is initially quicker and easier to employ staff to secure canes using plastic clips, but they 11 Typical plastic clips used to secure canes to wires

Old fruiting cane floricane being cut out higher and same time any unwanted primocane higher each year. growing around or between the plants removal and Secateurs, pneumatic pruners and can be cut out and thrown down in the loppers can be used for cane removal. alley for disposal. clearance Pruning black and hybrid berries, Where unwanted primocanes especially the trailing types, is gen- have not been removed, but allowed Whichever system of cane manage- erally more difficult and therefore a far to grow unchecked, it can be very ment and training is adopted, it slower and more expensive process difficult to reach the old fruited canes is best to start pruning out as soon than for summer fruiting raspberries. and primocanes that need removal, as harvest has been completed. The task is made far easier where: even with loppers. This will reduce the risk of disease spread from floricane to primocane, • Unwanted primocanes have been improve the air circulation and routinely removed throughout the Labour requirement improve pesticide spray coverage growing season. of primocanes, should it be neces- Cutting out and tying in should take sary. Early pruning and primocane • Primocanes to be retained to crop 6–15 hours per 100 metres of crop training can also hasten primocane the following year have been trained row with erect and semi-erect ripening, reducing the risk of cold up and secured onto the top wire blackberries. A similar output can injury during the ensuing winter. during the current growing season. be achieved for trailing black and Old fruited canes and any hybrid berries (assuming unwanted unwanted primocane should be In so doing, access to the base of primocanes have been removed cut through cleanly, as close spent floricane is improved. They and spring and summer training of as possible to the top of the plant’s should be cut out, detached from the primocane onto the support trellis has crown or at ground level. If the stubs trellis wires and thrown down into been carried out). This spring and are left, these can act as a source the alley. They can then be pulverised summer work can be expected to take of disease infection from cane blight. in situ, chopped and incorporated a further 6–10 hours per 100 m of They can also rub against primocane into the soil or removed. Removal is crop row, according to the plant habit, and damage the rind, leading to best achieved by gathering the canes in-row spacing and plant vigour. disease infection or produce egg lay- into piles with rakes and then pushing Where cane removal and training is ing sites for raspberry cane midge. them out of the alley, using a tractor not carried out earlier in the growing Tall stubs will also impede pruning mounted buck rake, and disposing of season, post-harvest or winter pruning in following years, with the spent them away from the plantation. At the can take considerably longer.

15 Biennial cropping How does it work? removed each time the plants are trained by staff during the Biennial cropping offers a completely In the fruiting year, all of the summer. Depending on the variety, different form of management primocane produced by the plant some 25–33% more primocanes where the growth of each plant alter- is removed as soon as it reaches are retained to crop than would nates between a fruiting (Figure 12) a height of 20 cm. In part, this be the case with annual cropping and vegetative phase (non-fruiting removal may be carried out using a plantations. In the late winter, just year) (Figure 13). This system offers a desiccant such as carfentrazone- prior to bud break, the new floricane range of benefits: ethyl (Shark), but more usually is tipped to remove any tissue that the unwanted cane is cut through has become damaged or diseased • Cropping plants are able to at its base using secateurs, removed during winter, only leaving canes produce significantly more from the row and placed down which have a diameter greater than fruit than plants which contain in the alley to wilt and die. In most that of a pencil. both flori- and primocane, as seasons, it will be necessary A biennial cropping plantation competition for water, nutrients to remove two or sometimes three may contain alternate rows of and light is removed. flushes of primocane until harvest cropping and non-cropping plants, begins and staff are no longer or the plantation can be split into • Fruit presentation and the rate available for this work. After harvest, cropping and non-cropping halves. of picking are greatly improved. the spent floricanes are left Separate plantations, with one or intact as are any primocanes that more varieties, in alternate cropping • Costs of cane management and have emerged. and non-cropping phases can pruning are reduced. In December or January, when also be used. the old floricane is dead and Plantations that are to be • Biennial cropping can break pest the primocane dormant, all canes managed biennially should be fully and disease life cycles, offering an are cut out, at or as close as established and at least 2 and opportunity to reduce incidence possible to ground level or the crown possibly 3 years old (having been and pesticide usage. of the plant. During the following annually cropped previously). They growing season, these plants will not should be free from any serious • Biennial cropping lends fruit, but produce two or three root or cane infections or weed itself to difficult to manage flushes of primocane. Suitable canes competition. Primocanes must be varieties such as Fantasia and should be selected, supported and provided with support to prevent those with a natural tendency tied onto the support trellis wires as wind damage throughout its growth towards biennial cropping they grow, so that by the end of the period, using strings or preferably such as Chester Thornless. growing season, they are in their final a pair(s) of mobile wires fitted to fruiting position for next summer. the support trellis. Ideally the plants Any damaged, weak, diseased or should be trickle irrigated and, if poorly positioned primocane can be possible, fertigated.

12 Biennial crop of ‘Silvan’ in the fruiting phase 13 Biennial crop of ‘Silvan’ in the vegetative phase

Whilst publications issued under the auspices © 2009 Horticultural Development Board. of the HDC are prepared from the best available No part of this publication may be reproduced in information, neither the authors or the HDC can any form or by any means without prior permis- accept any responsibility for inaccuracy or sion of the Horticultural Development Company. liability for loss, damage or injury from the appli- Feb 2009 cation of any concept or procedure discussed. Design and production: HDR Visual Communication