protea ing K Product: King protea Botanical name: Protea cynaroides Quality specifications for Australian wildflowers Product: Product: Cultivars: Cultivars: name: Botanical The spectacular king protea is a Protea flowers are rich in nectar and King protea King Seedlings, selections and named cultivars, including ‘mini kings’. ‘mini including cultivars, named and selections Seedlings, major cut flower. It is grown in many pollen, and as a result attract many countries and has a long flowering insects, which in turn can attract spiders. season. Like most proteas, it Leaf blackening following harvest can originates from South Africa. be a major problem. The severity of Protea cynaroides Protea this disorder varies between cultivars. The huge flower head consists of many Blackening can occur within 3–5 days of florets crowded together on the central harvest and greatly reduces the visual dome and is cupped by velvety bracts. appeal and vase life. The bracts are arranged in several tiers extending up the flower head, with The exact mechanism of leaf short, scaly outer rows and larger, more blackening is still not fully understood, attractive inner rows. but it results from the cut stem While there are many forms and drawing on the carbohydrate reserves cultivars, the most common king protea in the leaves to supply sugar in order has silvery pink bracts surrounding a to complete the development of the dome of silvery pink florets. There are also a white form and various other flower head. This leads to oxidation selections (pinkish to red). The flower and thus darkening of phenols within head varies in shape from a very wide the leaves. It occurs more quickly in inverted cone to a more narrow funnel warmer climates and in proteas stored shape. There are also several selections at warm temperatures and under low of ‘mini kings’ with smaller flower heads. light conditions. The leaves are generally large and rounded, and typically bright green. Florists like to use the lower leaves Flowering season: separately in arrangements. Most of the year, with a peak in July to December. Although flowers will not open if they are picked too early, the fully grown but unopened bud is acceptable in some Typical postharvest life: markets. 14 days. Export can reduce the vase life, especially if the transport conditions are not cold, the product dries out or transport takes too long. Other products to which this specification can be generally applied: Selections of Protea cynaroides, including ‘mini kings’. Market presentation - Sleeved vs no sleeve leading to damage Product: King protea STAGES OF OPENING Stage 2 Stage 3 Early stage: Ready to market preferred by (earliest stage): only a few 4–5 bracts still Stage 1 Immature stage with bracts markets, e.g. folded over tightly closed: unacceptable to markets for export dome CMND OM O EFECTS Common defects to avoid at market entry: n O vermature flower heads n D eformed, dull or poorly coloured flower heads n F lower heads damaged by birds or insects n D amaged bracts, e.g. insect chewing n D amaged leaves n L eaf yellowing or spotting Atypical flower head – may not be Yellowish leaves and bent stem n P resence of insects or disease acceptable to buyers – discard on flowers or leaves n D amaged bracts due to poor handling Leaf blackening – do not market Scale insects on leaves – do not market The stages shown apply to the product at market entry. Pay attention to the weather, time of year, and mode and duration of transport, because the flowers will continue to open during transport. STAGES OF OPENING You must consult with your target market to ensure that the flowers arrive at the desired stage. Stage 4 Stage 5 Stage 6 Ready to market Latest stage Overmature (latest stage): for domestic stage: prime stage markets unaccepted by for domestic many markets markets Damaged bracts due to poor Cold-damaged flowers Dull flowers (old stock) Torn leaves – discard handling – do not market (uneven opening) – discard – do not market Poor-quality leaves due to fungal Leaf spots; flower too open Deformed flower due to borer Insect contamination disease – discard – do not market or bird damage – discard (e.g. Monolepta beetle) – disinfest before marketing Product: King protea FLOWERS STEMS Appearance Flower head fully formed and at final size. Appearance Rigid and strong enough to support blooms, without Bracts opening evenly to reveal the central dome, with being too heavy and bulky. The Japanese market 4–5 bracts still folded over the dome (export markets prefers strong, thick stems. and if shipping to domestic markets in boxes). Bend <15°. Bracts reflexed to reveal central dome, and outermost Free of disfiguring trim marks or other blemishes. rings of florets open (for immediate domestic sale). Neatly cut end. Flower size proportional to stem length – market smaller heads on shorter stems. Length According to market demand, typically as Flower head follows in a straight line from the stem recommended in ‘Grading and bunching’ below. (and is not offset from the stem at >15°). Flower head not hidden by leaves. RECOMMENDED HANDLING AT HARVEST No bypass shoots or secondary blooms. Minimise drying out and exposure to heat – pick when it is cool, When to Flower mass (dome) firm and 10% or fewer florets preferably straight into buckets of clean water or a reputable commercial harvest open. postharvest solution, and hold in the shade. Move cut stems promptly to Flower head well coloured and typical for the a cool, shaded packing area. Cool quickly to remove field heat and stop selection. the blooms from continuing to open. Ensure cool room has continuous, uniformly bright light to assist in minimising leaf blackening (fluorescent Avoid harvesting when flowers are wet. lights need to be like very bright office lights to be effective). Damage No damaged bracts, or asymmetrical, deformed or GRADING AND BUNCHING damaged blooms. Discard any poor-quality product with insects or Flowers are generally marketed as single stems. fungal infections. Grading Grade quickly to minimise time stems are out of water. Contamination Ensure the flowers are free of grit and soil, weed seeds Reject any contaminated stems. or weeds, and signs of insects or spiders, such as Sort stems according to length and thickness: flower webbing. head proportional to stem length (typically 20%–25% Shake the stems over white paper to check what is of the total stem length for larger blooms). Market present, and take appropriate action to disinfest before smaller heads on shorter stems. sending to market, especially if exporting. Bunching Smaller flowers may be bunched in 5s with a single tie. Pests and No apparent pest or disease damage. The very large diseases and complex flower head makes insect disinfestation Stem length Stem length (cm) Length of flower difficult: earwigs, spiders and bees can be a problem. head (cm) A preharvest spray to chase out insects and spiders may assist. 100 18–20 LEAVES 90 15 Appearance Fresh; bright green. 80 14 Not dull or wilted. Minimum discoloration (<3% by area and affecting 70 11 <10% of leaves). No leaf blackening. 60 8 At harvest Do not harvest or store when foliage is wet. 50 6 Strip leaves from lower 10 cm or 1/3 of the stem, being careful not to damage the stem – cut with sharp 40 5 secateurs if necessary. Sleeves Use sleeves, especially for export product, to protect Damage Minimum evidence of pests, diseases or other bracts. A tight sleeve holds the bloom together and blemishes such as mechanical damage. Leaves entire makes flowers easier to pack. (no insect feeding damage). No scale insects, earwigs or spiders. No spider webs. Free of visible chemical residues. HOLDING AND STORAGE TRANSPORT Cooling Effective cooling soon after harvest is important to Refrigerated vehicle at 2–4 °C for long-distance transport. retaining quality and maximising vase life. There are two options: COMMON POSTHARVEST PROBLEMS Sydney ScienceScape Matthew Editing, by Stevens, • Edited Design Poppy Wild by JN: 9789 • Layout • Cool, process, cool – for example, remove field heat by Refer to Postharvest Manual* for general advice. cooling flowers immediately on entry into shed to 10 °C Insects Avoid postharvest dips. in buckets of solution, process flowers (bunch, grade), and then cool to 2–4 °C by either forced-air cooling (if boxed) (for export) Fumigate flowers before dispatch. Avoid fumigating at 20 or holding overnight in a cool room. °C or higher, or significant leaf blackening may result. • Process within 1 hour of cutting, and then cool to 2–4 °C Shake out any dead insects after fumigating and before by either forced-air cooling for 20–30 minutes (if boxed) packing. or holding overnight in a cool room (if in buckets). Ethylene King protea is not sensitive to ethylene. Forced-air cooling of packed flowers is ideal for large sensitivity volumes of product. Leaf Some growers recommend that in hot weather, plants Temperature Hold in a high-humidity cool room (95%) at 2–4 °C. blackening should be watered the night before picking, and that and humidity Another way of achieving high humidity is to cover the flowers be picked late in the day, after they have had flowers with plastic sleeves or plastic sheeting, as long as time to accumulate carbohydrates. there is no condensation on the leaves, which can lead to Careful postharvest handling will help reduce or prevent blackening. leaf blackening. Picking flowers when the foliage is dry Postharvest Postharvest solution: Hold in clean potable water with an (and keeping it dry), cooling them quickly after harvest added registered biocide. and storing them at 2–4 °C will help. Keeping cut stems solutions under continuous bright light may also help reduce its Pulsing probably does not benefit king proteas.