Maximise the orange, lemon and lime harvest from your garden or balcony.
I cannot imagine life without citrus… without zesty fresh juices full of vitamin c, more-ish lemon delicious puddings, a squeeze of lime in a soda or a Corona, or hot water with lemon to kickstart my mornings. Life would be so very bland without these things.
Citrus trees are some of the easiest fruit trees to grow in your backyard. Their popularity is deserved: they are ornamental yet productive, have handsome shiny green leaves and fragrant flowers, and they add wonderful flavours and zing to cooking. Equipped with my growing tips, you should be harvesting box loads in no time at all.
Citrus plants love sunshine – five hours a day is required for maximum fruiting. Planting them in a north-facing, warm and sunny position is best. In cooler climates, grow them alongside a sunny wall, where radiated heat will warm them; alternatively, bring pots inside during winter.
Citrus plants like water, but any water must drain away quickly and not pool in the root zone. to prevent this, before planting, dig a hole in a potential planting spot and fill with water; if it takes more than 30 minutes to drain, the drainage is inadequate. mound the soil or choose another spot.
Sunshine, quick-draining soil, airflow, infrequent deep watering and seasonal feeding are the keys to citrus success. In cold climates, plant the tree in spring when the soil has warmed up; in warm areas, trees can also be planted in autumn. Good soils improved with well-rotted cow manures, potash, blood and bone or a handful of garden lime each year will produce regular and reliable crops. Planting on mounded soil will prevent drainage problems, collar rot and fungal diseases.
Citrus trees have shallow feeder roots that need protection with mulching (the mulch shouldn’t touch the trunk) and feeding with citrus Peats Quality Blend Potting Mix throughout each season. mature trees need 5 kilograms of this mix along with a quality Citrus Food applied to the drip line each season.
Start young trees off with 5kg of Peats Quality Blend Potting Mix and build up the amount as they grow. When grown as a garden tree your citrus should be trained into four main branches. Open up the centre of the plant to increase airflow, and cut back shoots to a few buds after fruiting. Prune the young shoots to create bushiness. Choose a citrus grafted onto a rootstock suitable for your local environment and soil type. Trifoliata rootstock creates a dwarf tree, which is cold tolerant and resistant to collar rot, so ideal for heavy soils and cool areas. Citrange rootstock makes a faster-growing, taller tree, intolerant of poor drainage, so is ideal for coastal areas.
Citrus in small spaces
Do you want to grow citrus but don’t have the room for big trees? One solution is to train your citrus flat against a warm, north-facing fence, a technique known as ‘espalier’, but what I call my ‘gin and tonic wall’. Plant them at 1.2-1.5-metre intervals, about 30 centimetres from the fence. Tie the stems to horizontal wires along the fence and place the wires about 20 centimetres apart. This way the trees don’t encroach on the garden, but provide an evergreen screen to hide the fence. Growing a range of varieties along the fence means there’s always fruit ready to help kick off 6pm drinks.
Everyone with a spot of sun can grow citrus in a pot, but be aware they need constant care, feeding and watering to produce a healthy crop. Half wine barrels (or pots of a similar size) and quality potting mix are needed. Choose a citrus grafted to dwarfing rootstock Flying Dragon.
Potted citrus needs root pruning at least every three years. This entails pulling the the tree out of its pot, cutting five centimetres off the roots all around the root ball with a bread knife and replanting into the same pot with some fresh potting mix and citrus food. This will make all the difference to the number of fruit you will get the following season.
Flying Dragon is a dwarfing rootstock that limits the growth of the tree, but not the fruit, and is ideal for pots.
Those with more room can afford to plant a mini-orchard. The trees should be planted at two-metre intervals on mounded soil and grass should be kept well back from the trunk to avoid collar rot.
Citrus trees don’t need pruning to fruit well, but they may need pruning to fit in your backyard. Old trees benefit from a hard ‘renovation’ prune every 5-10 years after fruiting: remove dead wood, rubbing branches and inward-facing branches, and reduce all other branches by at least half. Removing the interior branches will open up the tree into a vase shape and get more light and air into the tree, thus reducing the risk of disease.
Yellowing leaves are a sign of iron deficiency, cold temperatures or lack of feeding. Feed with blood and bone, citrus food, iron chelates and sulphur simultaneously to combat this problem. Citrus leafminer is a little insect that makes small tunnels in new leaves; deter them and a range of other insects, such as sooty mould, scale and mealy bug, by spraying fortnightly with Eco Oil from spring until autumn.
Bronze orange bugs start life as a green nymph in spring, when control is easiest; use Eco Oil or Confidor. Citrus gall wasps lay eggs inside the outer branches, causing a deformed branch lump; treat by removing all branches affected with galls.