KG494 Print Combined

IMAGE Clockwise from left ChiccoDodiFC/Getty Images, Christina Vartanova/Getty Images, baianliang/Getty Images
Clockwise from left Have the best of
both worlds by growing citrus under
cover in winter and freeing up your
growing space by moving them
outdoors in summer; Greenhouse
shelving means you can bring in extra
little citrus plants over the coldest
months; In under-cover spaces careful
pruning is essential to create airflow.
Spacing
Dwarf citrus do best if planted 2m apart, but in a
greenhouse situation (especially if you are using
the space only to hold potted plants that will be
moved out over summer) you can close up the
gap a little. If you decide to do this, you will need
to keep the trees well fertilised and carefully
pruned to ensure adequate air movement
through the branches, and be on hand to manage
vents and windows.
Care
The secret to cosseting your under-cover dwarf
citrus is to slow down on the watering (although
a little each day is far better than a soaking every
week or two). And, contrary to what your instincts
might tell you about a fruit tree surviving through
winter, give the dwarf trees a little citrus fertiliser
each week to 10 days. If leaves are beginning to
yellow, feed with liquid magnesium chelate as it
assists the plants in taking up nutrients.
Although dwarf citrus will appreciate the heat
of a greenhouse in cooler regions, it won’t thank
you for significant fluctuations in temperature –
something that is very possible in the greenhouse
situation where one minute you have a frost
settling on the ground, and the next you have a
cloudless sky and heat beating in through the
plastic or glass. Create an even temperature by
attending to ventilation (use doors as well as
windows and vents, but be sure to net doors
where birds may prove a problem to the fruit).
Pruning
Pruning is essential if you are to keep the trees
small to allow for air circulation, and to ensure
they don’t reach beyond picking height (you
don’t want to be using ladders or standing
on chairs to reach fruit in your fragile glass or
plastic environment). A trim also increases fruit
yields and cuts down on the likelihood of heavy
branches snapping off with the weight of the
harvest. Pruning of under-cover citrus can be
done at any time of year, but late winter and
early spring is best. Whenever you decide to
do it, wait until after the fruit has set (in case
the delicate tiny fruitlets are knocked off or
you accidentally cut off a branch with young
fruit growing on it). If your trees are growing
in pots that are to be moved out when the
world warms up, think carefully about pruning
so that the plants will fit out the greenhouse
door (think “height” as well as “width”). As you
prune, try to cut out all but six of the lateral
branches, as this will encourage fruiting.
When pruning dwarf citrus, it’s important to
pay close attention to any suckers appearing
below the graft. The rootstock is quite capable
of throwing out these suckers and, before you
know it, the unwanted growth has taken over
from the grafted wood. If the graft is no longer
visible (as can happen when trees mature)
learn to recognise the rootstock by its sharp
thorns (another reason for snipping them off
sooner rather than later).
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