Growing Lemon Trees
- Select seeds from healthy mother trees for rootstocks
- Hot water treat seeds at 50° C for 10 minutes
- Seeds perform better when planted soon after they are extracted
- Sow seeds in seedbeds or polybags (18×23 cm). Seeds germinate in 2 to 3 weeks
- Water the seeds regularly, preferably twice a day until they germinate
- Seedlings are normally ready for budding when reaching pencil thickness or 6 to 8 months after germination.
- T-budding is the most common method.
- Do budding during warm months. Avoid budding during cold periods and during dry conditions
- Budded plants are ready for transplanting 4 to 6 months after budding
- Alternatively, obtain budded plants from a registered fruit nursery. These budded plants should be ready for transplanting in the field.
Transplanting in the field
- Transplant in the field at onset of rains.
- Clear the field and dig planting holes 60 x 60 x 60 cm well before the onset of rains.
- At transplanting use well-rotted manure with topsoil.
- Spacing varies widely, depending on elevation, rootstock and variety. Generally, trees need a wider spacing at sea level than those transplanted at higher altitudes. Usually the plant density varies from 150 to 500 trees per ha, which means distances of 4 x 5 m (limes and lemons), 5 x 6 m (oranges, grapefruits and mandarins) or 7 x 8 m (oranges, grapefruits and mandarins). In some countries citrus is planted in hedge rows.
- It is very important to ensure that seedlings are not transplanted too deep.
- After transplanting, the seedlings ought to be at the same height or preferably, somewhat higher than in the nursery.
- Under no circumstances must the graft union ever be in contact with the soil or with mulching material if used.
Tree management / maintenance
- Keep the trees free of weeds.
- Maintain a single stem up to a height of 80-100 cm.
- Remove all side branches / rootstock suckers.
- Pinch or break the top branch at a height of 100 cm to encourage side branching.
- Allow 3-4 scaffold branches to form the framework of the tree.
- Remove side branches including those growing inwards.
- Ensure all diseased and dead branches are removed regularly.
- Careful use of hand tools is necessary in order to avoid injuring tree trunks and roots. Such injuries may become entry points for diseases.
- As a general rule, if dry spells last longer than 3 months, irrigation is necessary to maintain high yields and fruit quality. Irrigation could be done with buckets or a hose pipe but installation of some kind of irrigation system would be ideal.
- [listitemCitrus is under irrigation in the major citrus world producing countries.[/listitem]
Manure and fertiliser
For normal growth development (high yield and quality fruits), citrus trees require a sufficient supply of fertilizer and manuring. No general recommendation regarding the amounts of nutrients can be given because this depends on the fertility of the specific soil. Professional, combined soil and leaf analyses would provide right information on nutrient requirements.
In most cases tropical soils are low in organic matter. To improve them at least 20 kg (1 bucket) of well-rotted cattle manure or compost should be applied per tree per year as well as a handful of rockphosphate. On acid soils 1-2 kg of agricultural lime can be applied per tree spread evenly over the soil covering the root system. Application of manure or compost makes (especially grape-) fruits sweeter (farmer experience).
Nitrogen can be supplied by intercropping citrus trees with legume crops such as mucuna, cowpeas, clover or dolichos beans, and incorporating the plant material into the soil once a year. Mature trees need much more compost/well rotted manure than young trees to cater for more production of fruit.
It is recommended to use organic fertilizers.
In windy areas, a windbreak should be provided as citrus is sensitive to strong winds. A windbreak provides protection at orchard tree level for about 4-6 times its height.
- Plant the windbreak as close as possible and at right angles to prevailing winds.
Symptoms of mineral deficiency
|Nutrient Element||Leaves||Fruit||Tree growth|
|Nitrogen||Pale yellow to old ivory||Reduced crop||Reduced.May produce abundant bloom.Flower buds may fall without opening|
|Phosphorous||Small, dull||Reduced crop. Large.Puffy, bumpy surface,enlarged core cavity andthick rind.||Reduced|
|Magnesium||Yellow mottling along marginDeveloping a green wedge to “Christmas tree” pattern.Eventual complete yellowing and defoliation.||Reduced crop||Reduced|
|Iron||Yellow veins, remain green untilfinal stage of general chlorosis.Reduced size||Reduced crop||Eventually reduced|
|Zinc||Mottled yellow between main veins.Small narrowEarly fall.Reduced size||Reduced crop,some pale yellow off types||Eventually reduced|
|Manganese||Normal green along main veins.Rest of leaf pale green to light yellow||Reduced crop||Eventually reduced|
|Potassium||Old leaves curl and loose their green colour||Small, smooth, thin rind,drop prematurely||Reduced|
|Copper||Deep green, oversized, then darkened||Splitting and gumming.Dark brown gum soaked eruptions.May turn black.Gum in centre core||Twigs enlarge at nodes,blister and die back.Gum pockets.”Cabbage head” growth|
Lemon Rootstock (Local Lemons only)
Collect seeds in March/April – Use local lemons and remove seeds and dry in the shade on a
mat or black polythene
Sow: April/May since they are slow growers. Plant one seed per tube
Seed: Polyembryonic. (The seed has two embryos and can produce two shoots. If this happens
remove one shoot and replant in another tube)
Sowing depth: Sow in the tubes and cover with a thin layer of the soil mixture (maximum of half
Watering: Morning and afternoon each day
Ready for Budding when the seedling reaches the size of a pencil normally after 5 months-October