Support system, planting & initial pruning
Choose an open, sheltered position, avoiding frost-prone sites, if possible. Soils should be well-drained, moisture-retentive and not prone to waterlogging.
The best time for planting cordons is in winter. Use one-, two- or three-year-old cordons. When buying cordons, you will have a choice of rootstocks. Use M27 rootstock (extremely dwarfing) or M9 rootstock (very dwarfing) for apples where the soil is fertile; otherwise, use M26 rootstock (dwarfing). Pears are best grafted on Quince C or, for very poor soils, Quince A. If in doubt, use a more dwarfing rootstock as it is always possible to boost vigour with watering, feeding and mulching if required.
Support system
Cordons need a permanent support system made up of three horizontal wires 60cm (2ft) apart with the lowest wire 30cm (1ft) from the ground. If planting against a wall or fence, fix the wire using straining eye bolts that will let the wire be fixed not less than 10cm (4in) away from the structure to allow for air circulation. Keep the wire taught with straining bolts available from fencing suppliers. Use a sturdy 2.5mm, gage 12 galvanised wire.
If using posts, the posts should protrude 1.8m (6ft) from the ground with about 60cm (2ft) below ground, spaced 2.2-3.5m (7-12ft) apart. The end post should be strutted. Fix bamboo canes diagonally to the wires for the trees to be trained on.
Plant trees at an angle of 45 degrees. If planting more than one cordon, space at 60-90cm (2-3ft) apart. The wider spacing within the row is for infertile, shallow or sandy soils. Tie the cordon to the diagonal bamboo cane fixed to the wire support with a soft string. Cordons can be allowed to reach a height of about 1.5-2m (5-6½ft) so take that into consideration when planting.
After planting, cut back all laterals (side shoots) longer than 10cm (4in) to three buds, leaving the leader and any short laterals unpruned.
Vertical and double cordons (‘U’-shaped) can also be grown in containers (at least 45cm (18in) wide) in John Innes No. 3 compost (a soil-based potting media that is easy to manage and heavy enough for the pot to be stable).