Getting to the root of the problem
ACOUPLE of weeks ago a bloke fairly new to growing vegetables asked me to explain why he was unable to grow decent parsnips.
He insisted he’d “done all the right things” before sowing the seed, but his efforts were a constant failure.
His plants produced plenty of huge leaves, he told me, but when they were pulled from the ground there was virtually nothing down below.
In short, his parsnips were all top and no bottom.
When I asked him what he meant by “doing the right thing” he went into some detail to explain how thoroughly the soil had been dug and heavily manured.
He was genuinely mystifi ed by this continuing failure to grow decent parsnips.
This inability of many vegetables to form decent, edible roots is a common problem.
The same problem can occur with carrots and beetroot.
This excessive, top- heavy leafi ness is caused by over- rich soil conditions.
Parsnips are particularly sensitive to over- manuring.
It is why the seed should always be sown into soil that has not been recently manured, especially with high- nitrogen fertilisers.
I always sow carrot, parsnip and beetroot seed into soil which has been fertilised at least a year earlier to produce crops of leafy vegetables such as brassicas, lettuces or silverbeet.
This slightly impoverished soil allows most root- crops to send down deep roots that swell rapidly. That’s the part we love to eat. I should add that it is already too late in most parts of Tasmania to sow parsnip seed.
If sown this weekend it will be early April before the seedlings appear and virtually impossible for them to fully mature.
It is possible in warm districts to succeed carrot and beetroot seed, although the roots may be slightly small.
Organic growers never feed their plants anyway – they feed the soil.
This allows plants to take up precisely the right amount of nutrients they need as they grow and increase in size.
The greediest of all vegetables can be planted out now as strong seedlings.
They include cabbages, caulifl owers, broccoli, silverbeet and lettuces.
All grow strongly in soils enriched with high- nitrogen fertilisers.
Among the best natural fertilisers with highnitrogen content are poultry and other bird manures with the strongest of all being pigeon droppings.
However, all bird droppings must be used cautiously.
If too fresh they can produce serious problems and either kill or damage plants.
This is often mistakenly described as “fertiliser burn”, the implication being that extrastrong manures actually burn the roots of plants.
This misconception arises because the leaves of damaged plants usually begin to shrivel and take on a burned appearance.
However, the real cause is moisture loss because over- fresh manures actually draw moisture away from plant roots.
Fresh horse manure salvaged from stables can also be destructive, especially if mixed with straw bedding.
This is because it is soaked with urine and it is this concentration that causes most damage.
I once saw a rose garden virtually destroyed because someone mistakenly spread a thick layer of fresh stable manure between and around the rose plants.
All the leaves started to wither and turn black.
The only way the rose plants were saved was by applying heavy irrigation to completely saturate the soil.
The extra water diluted the urine and also helped fl ush it away from the rose roots.
The best way to utilise fresh manure of any kind is to mix it with any kind of soft organic matter such as straw, leaves, wilted weeds or grass clippings.
The stack can be given a good watering; covered with a sheet of black plastic to keep out the rain and left to decompose.
In a couple of months it will have rotted down and become compost.
This is a perfect fertiliser, ready to be worked into the soil.
However, just make sure you don’t make the blunder of sowing parsnips, carrots or beetroot there.
DON’T OVERDO IT:
Parsnips are unlikely to grow if the soil they are planted in has too much manure.