Page 33 - Simply Vegetables Summer 2023

By October, growth for the season will be finished, and the foliage will gradually die down. The roots may then be used, lifting with a fork as they are required. In the event of hard frost occurring a coating of leaves or litter may be spread over the roots to secure them. No useful purpose
is served by leaving them in the ground after February, as growth then begins, so whatever then remains should be lifted and used up as required.
It requires no prophetic vision to predict
a great scarcity in foods during the next few years, and he who lays his heart and soul into the work of food production – be it on the back yard, the allotment, or the broad acre scale is a benefactor to the nation; that is the spirit in which the notes on the prosaic parsnip are written Editors Comments.
It is interesting to see how language has changed over the last century and modern magazines have a different style. The
early sowing in February is now not often followed even with climate change and most people sow their parsnips in March. It is good to see mention of deeply working the soil, none of this no-dig nonsense in those days! The comment about rain being a nitrogenous stimulant is interesting and
I presume this was their thinking in those days, certainly if lightening is present
the rain can contain some nitrogen but otherwise rain can wash the nitrogen out of the soil.
Tephritis onopordinis this appears to be a type of leaf miner similar to celery leaf miner although I have not found much information on it. If it is a leaf miner these days you would live with it as they do little damage unless they are a problem in Eire (If any Irish members are familiar with this pest please let me know).
Quassia used to be an organic spray
for pest control, but I believe is not longer approved but can be used for nit control in the hair and also on pets! Bordeaux mixture is also banned in the U.K and Europe now so should not be used.
The varieties stated were readily available until recent years and are now considered to be heritage varieties, I can remember sowing them in my younger days, not 1918
I might add!.
Root pruning of top fruit trees
The root pruning of some top fruit trees to encourage the tree to produce flowers and then fruit is an old technique that has been used for many years and was occasionally referred to in old gardening books and magazines.
But I have not seen or heard anything about it for a few years now and assumed it was no longer recommended until I recently saw a report on some research carried out in Kent in the early 2000’s. Following that I found some American research carried out at about the same time saying that it was being used by some growers on good soils to encourage better fruiting.
The British research suggested that it was still a possible alternative method to “shock” apple and pear trees into fruiting. Root pruning is a fairly drastic method and should not be carried out lightly, before trying it try feeding with high potash feeds for a year or two and some controlled pruning to reduce vigorous growth and encourage flowering. Summer pruning will tend to encourage the production of fruiting
spurs rather than growth
which winter pruning
does. If after trying this
fruiting has not improved,
then give root pruning
a go.
time as this also helps control the size of large fruit like the cultivar Jonagold.
When digging the trench use a sharp spade and dig carefully, very small roots can be cut using the spade but any roots over 1cm should be cut cleanly using loppers or if large a pruning saw. Once the roots have been cut backfill the
hole with good soil and include some well-rotted organic matter and a handful of fertiliser in the backfill to encourage the tree to produce fibrous roots in the backfilled trench.
Commercial growers try to cut the tap roots by using an offset sloping blade that cuts partly under the tree, but this can
be difficult when hand digging without making the tree unstable. Aim to cut approx. half the tree circumference and see how the tree reacts, if there is no improvement do the other half of the tree the next winter.
It is likely that during the following summer the tree may need watering as it will have less roots to search for and uptake water, also applying a mulch
Commercial growers
root prune by pulling a
blade behind a tractor
that cuts the tree roots
so it is not too difficult but for home growers you will have to dig a trench to access the roots to cut them. The trench should be a spade width and 30 to 45cm deep, in most cases a 30cm deep trench should suffice. The trench should be
on two sides of the tree although in the past it was dug all around the tree. The distance for the trench from the tree can vary depending on the size of the tree, the rootstock, and cultivar as some are more vigorous than others. The American research stated a useful guide was for the trench to be approx. 2⁄3rds of the distance from the trunk to the edge of the tree canopy. The British research indicated for small trees the inside of the trench can be 50cm to 1metre from the trunk and larger trees 1 to 1.5 metre away. The closer the trench to the trunk the greater the control on growth and the more it will stress the tree.
Root pruning should be carried out between November and February when the trees are fully dormant and at least 6 weeks before the buds start to grow. Pears are better root pruned before Christmas. Interestingly the Americans were stating to root prune at flowering
Root pruning helps to control excessive vigour and encourage flowering
around the tree will help to conserve water and reduce weed growth.
Root pruning helps
to control excessive vigour and encourage flowering and therefore fruiting other advantages include increasing the light penetration into the tree crown which give
better fruit ripening and colour, improves spur quality and is reported to reduce fruit drop near to harvest time. It was also reported in the American research to increase fruit firmness, reduce bitter pit, reduce fruit size (which is useful for large, fruited cultivars but not smaller ones!) and reduce shoot growth and trunk diameter. If your trees have a habit of biennial bearing (that is fruiting heavily every 2 years and hardly any fruit in alternative years) root pruning may help to reduce this if the root pruning is done the winter after the heavy year.
If after root pruning the tree appears to be a bit unstable especially during windy weather, it may pay to stake the tree for a couple of years.
It appears that root pruning may be coming back into fashion and is worth a try if your apples or pears are not fruiting well, but remember it is a fairly drastic method and will stress the trees. Other top fruit trees can be root pruned but the research was ongoing and there are risks if using it on plums, cherries, and similar stone fruit so with these it should be a last resort before grubbing out the tree and you have nothing to lose.
Simply Vegetables 33