Greengage

Established greengages are hardy and get through winter outdoors without protection in the lowlands of Germany, Austria and Switzerland. In the first years, wrap the young trunk over winter with a hessian strip or a coconut-fibre mat against winter desiccation, and mulch the tree base with leaves or bark material against hard ground frost.

Greengage varieties are genetically heterozygous: pips grow into seedlings that do not come true to variety. For named varieties (for example ‘Graf Althans’, ‘Oullins Reneklode’) grafting onto a rootstock is the only reliable method.

Grafting (main method): from July to mid-August, bud a dormant bud (T-budding) onto a one-year-old rootstock. Proven choices are the vigorous myrobalan (Prunus cerasifera) for normal to drier soils, or less vigorous rootstocks such as ‘St. Julien A’, ‘Wavit’ or ‘Brompton’ (Brompton prefers heavy, moist soils and, unlike myrobalan, does not form root suckers) for smaller trees. Cut a ripe shoot of your chosen variety, remove all leaves straight away except a short stub of leaf stalk as a handle, and slide the bud under the loosened bark of the rootstock. Bind it tightly with budding tape. After one to two weeks, a leaf stalk stub that falls off easily shows that the bud has taken; then you remove the tape. The following spring, shortly before growth starts, cut the rootstock back just above the established bud. As a spring variant, hand grafting (whip-and-tongue grafting onto a dormant rootstock, roughly January to March) works with scions stored cool. Note: plum grafts knit together somewhat less well than, for example, apple, so work cleanly and quickly.

Hardwood cuttings (supplementary method): with wild types or less variety-bound plants, you can cut ripe, pencil-thick shoots (15 to 20 cm) in autumn, slanted at the bottom and straight at the top, and heel them into sandy seed compost in a frost-protected, bright place. Rooting is possible in principle with Prunus domestica, but the success rate is clearly lower than with gooseberry or currant. For valuable greengage varieties, grafting is therefore clearly preferable.

Note on root suckers: some old plum varieties used to be propagated on their own roots by root suckers; but that only works with own-root trees. Since greengages are almost always grafted onto a rootstock, their suckers come from the rootstock and not from the cultivar; they are therefore not true to variety and unsuitable for deliberately propagating a greengage.