PLANTING & SOIL
Citrus are shallow rooted trees which like good drainage & plenty of sun. They will grow in most soils except poorly drained, wet ones. If a young lemon tree is carrying a lot of fruit, or even a lot of flowers & buds, prune or pick most of them off as they will retard growth & cause leaf yellowing & shedding.
PESTS & DISEASES
Scale is common on citrus, especially in summer. Ants can often been crawling up the trunk to get the sugars produced by the scale which are oval shaped bumps adhering to the stem and leaves. Eco oil should be sprayed over the whole tree. Eco oil is safe and effective. Do not spray if temperatures are over 25 degrees.
REASONS WHY LEMON TREES (& OTHER CITRUS) CAN LOOK SICK...
End of winter usually produces some yellowing especially in younger trees. Too many buds & fruit, mainly in younger trees, can lead to yellowing & leaf drop. Remove buds & fruit and feed moderately in spring. Poorly drained soil or wet feet can cause yellowing & shedding of leaves. Lack of food and/or water. Usually in late spring or summer. Feed with citrus or complete fertiliser (not in pots). Use slow release fertiliser if in pots. Harrys citrus food has shown fantastic results. Water frequently in summer as citrus are surface rooting.
PRUNING & REWORKING
If plants have dried out or shed leaves & look straggly, they can be pruned hard (or lightly) as desired. Spring & summer are the best times for this. Some fruit or flowers might have to be sacrificed, however it’s worth it if a thick, bushy tree is required. Citrus can be almost leafless & still recover if pruning, feeding & watering are attended to (unless the problem is poor drainage or Collar Rot).
Lisbon: Thick skinned, long bearing variety, usually thorny, medium height, strong flavour & good in Melbourne climate. Also not bad in clay soils. There is a thornless variety.
Eureka: Mostly thornless, good in cooler climates, more summer bearing than other types, well drained soil.
Meyer: Thin skinned variety, almost a cross between an orange & lemon, sweeter taste, cold tolerant, smaller growing & not very thorny. Better for tubs. A warm sheltered position required.
Navel: thin skinned, seedless. Bears in winter & early spring.
Valencia orange late spring/early summer bearing. Also for great for cooler districts.
Prone to alternate bearing. This may be reduced by thinning heavy crops (up to 25%). Fruit should not be left to ripen too long on the tree. Imperial is a good variety.
Warm sheltered position in Melbourne.
Sensitive to frost. ‘Tahitian Lime’ is best in Melbourne.
Leaves are used in Asian style cooking.
A Highly ornamental small tree which is more cold resistant than other citrus. Fragrant flowers & attractive small, bitter orange fruit, suitable for marmalade. Excellent in tubs.
GROWING CITRUS IN POTS
All citrus can be grown in tubs. The bigger the tubs, the better. Citrus are thirsty plants so need plenty of water, good quality potting mix, regular feeding and pruning.