| Planting your citrus orchard
With the size of the average home garden
these days at about 0.1 hectare, few of us will plant an orchard. More likely a few trees
at best. Unless you have plenty of sun, with lots of air moving past the site where you
want to plant citrus, forget it. Plant something else. I have however seen some
enterprising gardeners who move their citrus containers around, to catch the maximum
winter sun and protect them from the odd frost. I forgot to mention the need to more a
potted kumquat around, in a house that I vacated last year, so that the frost wouldn't
kill it. They didn't and it did. I'd nurtured that kumquat for 12 years in frosty Stirling
SA, but one solitary frost took it out, because it had been left more than a metre from
it's protecting wall.
Lesson number one... citrus hate frost. Sure the tangelo is
more frost resistant than almost any other citrus and the 'Lisbon' lemon will recover from
-2_C of frost, but generally a heavy frost is terminal on citrus plants, unless you can
engage some protective measures. Those might be as simple as moving your containers or
spraying your trees before dawn with water so that the sun's early rays don't rupture the
frozen plant cells as they thaw. That's what does the damage. The water from your hose
will be relatively warmer than the frosted leaves and so it thaws more slowly than the
sun, without damage or with much less damage. That's why the water cannons are going
gun-busters pre-dawn on frosty mornings in the Sunraysia.
The minimal soil preparation for planting citrus, is to dig
a hole at least three times the size of the container from which you are going to extract
the plant. ISo if you buy an orange plant in a 255mm (10") container that has a four
litre capacity, the smallest acceptable hole to prepare for it, would be a twelve litre
capacity hole. That allows for the root run for one year. Into that hole add some well
rotted compost or shredded copra, if no compost is available. I stress copra because the
compressed bricks are readily available these days and they alleviate the need for the
non-renewable resource of peat moss. Compost or copra aid the nutrient uptake for your
young plant. On heavy clay soils remember the gypsum to open up the soil structure and use
a fork not a spade on wet soils. The spade leaves a polished soil cut that makes root
penetration difficult and moisture movements impaired, where as the fork leaves a rough
cut that aids the root run.
If you are planting onto wet or seasonally waterlogged
soils, build a small
mound of about 10cm high and level it off so that at least
10cm of the root run of the newly planted citrus will always be above the saturated water
level of the soil. On well drained soils this is not necessary. Be sure to plant the
citrus so that the bud union is clear of the soil surface and that there is no organic
material up against the trunk, since this causes the stem to rot. Citrus do not like leaf
litter or compost against their bark and lemons in particular develop collar rot very
quickly if organic material is left against their bark for too long. The remedy is to
remove the organic material first then daub the stem with a slurry of the contact
fungicide, Bordeaux mix.
Having prepared your planting hole and planted your tree,
the question often arises as to whether you need to tease the roots out at planting time.
Kumquats in particular resent this action, but most other citrus benefit from a light
teasing and then backfill the plant as you plant it, drawing it up as you plant it. That
gets the friable soil worked back in around the roots. Then tamp in with your hand and
water immediately to remove any air cavities or else some of the tiny feeder roots might
dry out, causing stress.
The timing of planting is a constant source of debate.
Citrus in southern states tend to be sold at the same time as open-rooted fruits and nuts,
in winter. My experience is that they grow better if planted in spring as the soils are
warming up. In the sub tropical regions they will make growth when ever water is applied,
so that greatly extends their planting seasons.
It is most important to keep the weed competition down when
you are establishing young plants. The weeds not only deplete soil moisture, but also rob
the soil of available nutrients. You can either resort to lots of elbow grease and
physical effort or use a glyphosate spray as a knockdown herbicide every two months. Spray
in the still of the day. Glyphosate, leaves no residues in the soil and is only an amino
acid that breaks down the molecular structure of the chlorophyll in the weeds, so they
collapse from exhaustion. Make sure not to get any on your citrus plants or they will show
some leaf burn, since glyphosate is not selective in what it kills. Most proprietary
brands of glyphosate, such as Roundup®, Zero® and No-Grow® contain a toxic surfactant
or spreading agent, that is rated |
