50 W Horticulture {Hortmag.Com}
Total Page:16
File Type:pdf, Size:1020Kb
50 W HORTICULTURE {HORTMAG.COM} 0416Feature_MixandStitch.indd 50 1/19/16 2:48 PM Multi-grafted trees make it possible to grow many varieties of fruit in a small space words and photographs by Lynsey Grosfi eld ’ve begun to affectionately refer to my graft- ing projects as my Frankentrees—not just because they are occasionally hideous, but be- Icause they’ve become quite a bit more complex than the standard “rootstock + scion” fare. My penchant for amateur tree surgery began in 2013, as I started getting serious about the idea of cultivating a back-yard food forest. I found myself totally unable to reconcile the diversity of cultivars I wanted to try with the square footage of the lot in which I was working. Where space is at a premium and desire for agricul- tural diversity is high, multi-grafted Frankentrees are the home orchardist’s salvation. HORTICULTURE {HORTMAG.COM} E 51 0416Feature_MixandStitch.indd 51 1/19/16 2:48 PM 52 W HORTICULTURE {HORTMAG.COM} 0416Feature_MixandStitch.indd 52 1/19/16 2:48 PM The author is experimenting with grafting multiple species and cultivars of fruit trees. Her Tree of Red-fleshed Apples (opposite page) combines nine cultivars. Finding healthy scion wood of pears like ‘Winter Nelis’ (left) and ‘Fondant du Comice’ (right) has taken sleuthing. I started tracking down scion In the nursery trade, trees graft- MATCHMAKER, wood from all sorts of desirable heri- ed with two or more cultivars are MATCHMAKER tage cultivars of apple, pear and stone marketed as a way to ameliorate The rules for grafting are plastic, fruit (Prunus spp.), and I tried my the problem of pollination partners. within reason. Interclonal/intraspe- hand at grafting for the fi rst time. As Customers who want a productive cific grafts are very nearly always a self-taught horticulturist Googling harvest from a self-sterile cultivar compatible; interspecific/intrage- grafting tutorials and trawling eBay can purchase a double-grafted tree, neric grafts are usually compatible; for scion wood, I’ve found the learn- guaranteeing that genetically dis- intrageneric/intrafamilial grafts are ing curve steep, but my projects have tinct pollen lies well within cross- seldom compatible; and interfamil- become something of an obsession. pollination distance. It’s an easy ial grafts are essentially always in- I was inspired by Sam Van Aken, choice for circumscribed spaces of compatible. That said, individual an art professor from Syracuse Uni- cultivation with unknown neigh- cultivars within broadly compatible versity who grew up on a farm in borhood plant genetics within bee- groupings may reject a graft for a Reading, Penn. When the New York foraging range. But for the more variety of reasons, sometimes reduc- Agricultural Research Station was industrious back-yard orchardist, ible to mere genetic incompatibility, closed because of budget cuts, he a multi-grafted tree can go well the season in which the graft was bought part of it. The station hosted beyond the conventional two to accomplished, environmental condi- all manner of heirloom and heritage five cultivars. The tree on which tions, poor craftsmanship or disease. stone-fruit cultivars and species. one practices grafting can become The keys to success, then, are trying Using chip budding, he began mak- a truly monstrous multi-year proj- often, trying in the right season and ing multi-cultivar trees of peaches, ect and a back-yard source of fruit using hygienic methods. plums, apricots, nectarines, cherries salad. My practice tree, a crabapple For example, apples (Malus spp.) and almonds, eventually imagining I topped to induce the growth of can usually be grafted together. This his now-famous Tree of 40 Fruit water sprouts, has turned out to doesn’t mean the domestic apple project. Each multi-grafted tree is a be surprisingly successful: It now (Malus domestica) must be grafted reservoir of plant genetics, many of boasts 10 diff erent successful grafts, with the same; it can pair with a which are forgotten in the industri- which will yield 10 diff erent kinds Siberian crabapple (Malus baccata), alization of orchard production. of apples. the wild Caucasian Niedzwetzky’s Where space is at a premium and desire for agricultural diversity is high, multi-grafted Frankentrees are the home orchardist’s salvation. HORTICULTURE {HORTMAG.COM} E 53 0416Feature_MixandStitch.indd 53 1/19/16 2:49 PM Above: A sign of a successful graft comes when the scion—the wood grafted onto the rootstock—begins to put out new growth, as seen on this pear. Opposite page, left: An upclose look shows scion and rootstock where they have healed in a wedge graft made by the author. apple (M. niedzwetskyana), the Japa- maximal compatibility, but suffi ce it a ‘Makamik’ crabapple, a Canadi- nese Sargent’s crabapple (M. sargen- to say it should be possible to cobble an cultivar that arose as an open- tii) or any combination of these and together a tree that produces every- pollinated seedling of M. niedz- more. The possibilities are contained thing from almonds (Prunus dulcis) wetskyana. My ‘Makamik’ was itself within the genus Malus, rather than to sweet cherries (P. avium)—Sam grafted on a dwarfing rootstock. I narrowly along the lines of species. Van Aken seems to have accom- top-worked that tree—using a sim- Similarly, pears (Pyrus spp.) are plished as much. ple cleft graft—at one meter off the normally compatible with other Citrus fruits (Citrus spp.) fall ground to include two Gravenstein pears. This means European pears out of range for me to cultivate, but apples: both the original ‘Graven- (Pyrus communis) can be grafted they’re reportedly candidates for an stein’ (interestingly, one of the fi rst with Asian pears (P. pyrifolia). Com- array of grafts. The Fruit Salad Tree triploid apples, meaning it has three plicating the picture, though, pears Co. in Australia boasts a tree that will sets of chromosomes) and a sport of are often grafted on a dwarfing yield oranges, mandarins, lemons, that tree, ‘Red Gravenstein’. quince (Cydonia oblonga) rootstock. limes, tangelos, grapefruits and pom- The ‘Makamik’ parts of the tree Even more confusing, “quince” also elos. Citrus species can also be made have maroon leaves that fade to a refers to two other closely related more hardy to cold by being grafted deep green and bright pink blossoms, genera: Chinese quince (Pseudocy- onto a rootstock of a close relative: while the ‘Gravenstein’ branches leaf donia sinensis), and three species of trifoliate orange (Poncirus trifoliata). out in the brightest shade of green Japanese flowering quince (Chae- and bloom white. I’ll further ma- nomeles spp.). While the latter two FRUITFUL FRANKENTREES nipulate this tree with many more may be able to be grafted together, Beyond my practice tree, I have a scions as it grows, to add new leaf they may or may not be compatible few multi-grafted apples and pears and flower colors in addition to a with pears. gracing my garden. Stone fruit hasn’t diversity of pollen and fruit. Stone fruit (Prunus spp.) require been my forté, but I’m continuing to With the success of that small some trial and error. I am sure there learn the tricks of the trade. It is a project, I moved on to creating my is an algorithm that could chart op- work in progress. Tree of Red-fl eshed Apples. This one timal placement of scions to ensure My first real success came on has been a middling success, but I 54 W HORTICULTURE {HORTMAG.COM} 0416Feature_MixandStitch.indd 54 1/19/16 2:49 PM Above right: This tree combines three apples—‘Makamik’ as the rootstock, with ‘Gravenstein’ on its left branch and ‘Red Gravenstein’ on the right. The three varieties offer new leaves and flowers of different colors and provide a diversity of pollen and fruit in a small growing space. intend to try and re-try graft combi- opens it to pathogens bacterial, fun- that thrive in a given biome. Appro- nations until everything sticks. The gal and viral. Certain cultivars, es- priate cultivar selection is impor- base tree was a ‘Circe Redlove’ ap- pecially older specimens, will be tant to begin with, but failure is just ple—recently released by the Swiss more vulnerable to certain diseases. as informative as success. fi rm Lubera—grafted on a dwarfi ng The scion wood itself must come A Frankentree also improves rootstock. I tracked down several from a sterile source, because dis- overall pollination and provides scions of apples known to produce eases like plum pox and apple mo- longer windows for both blossoms pink or red-fl eshed fruit: ‘Red Devil’, saic virus are readily transmitted and harvest. A longer flowering ‘Bloody Ploughman’, ‘Sops in Wine’, through grafting. window prolongs the beauty and ‘Scarlet Surprise’, ‘Baya Marisa Tick- Every grafting site where tis- better feeds the bees. Smaller har- led Pink’, ‘Mott’s Pink’ and ‘Moun- sues have inosculated can become vests of diverse fruits over a longer tain Rose’. Many of these have M. swollen or brittle over time. Graft- period of time suit the back-yard niedzwetskyana genetics, as the pink ed joints, like scar tissue, consti- orchardist much better than an ava- fl esh predominates in that species. tute weaknesses in the scaffold of lanche of virtually identical fruits. Trying to create a broad, open the tree. Further, the maintenance Most importantly, however, it’s scaff old, I top-worked these scions of the tree itself becomes more fun! Grafting a tree with an abun- on the extremities of the ‘Redlove’ complicated, as some scions will dance of scions creates a sort of apple, using simple whip and tongue be more vigorous than others and living sculpture, and it becomes a grafts.