by Wally Richards

MARCH GARDEN PROBLEMS

Stress in plants is very similar to stress in people: when we are under stress our immune systems are weakened, we are more likely to catch colds and have other health issues.

Stress in humans comes with side effects, such as b eing unable to obtain a good night’s sleep, rushed meals or fast foods and the digestive system does not operate as well as it could; our body functions are under pressure.

 Thus our original stress condition is compounded with the resulting side effects.

Similarly when a plant comes into stress at this time of the year because of the hot dry conditions, it is also weakened, attracting pests and diseases, who’s job in nature is to assist in taking the weak plants out.

The plant goes into reproductive mode, flowering profusely and setting seeds.

As the plant’s life is threatened, it just wants to produce offspring and most, if not all its resources go into this. (In dry times you might see weeds a few centimeters tall flowering and going to seed because they are protecting their DNA.)

To make matters even worse, the soil life, including the worms, will have insufficient moisture so they disappear and reduce further the plant’s ability to take in nutrients and moisture.

Sap sucking insects compound the problem and diseases such as black spot, rust and mildews run wild.

To illustrate a point, a few years ago I had two areas of garden with silver beet growing, one right down the back, fenced off from the free ranging chooks, which was planted up in late spring. The area is very dry with a heavy clay soil and a number of established trees which also suck most of the available nutrients and moisture out of the soil.

It was not a good gardening area. I did not water as much as I should have done, and the silver beet was poor looking with rust problems and going to seed.

In the other area I had a raised bed with ample compost and animal manures in it. This area was planted with silver beet seedlings in mid-January and each night I would give the bed a nice drink of filtered water (non-chlorinated) with a handheld hose.

Here the silver beet was lush and already ready to harvest the outer leaves.

No rust, just happy plants that have no stress problems. Worms were active which told me that all the soil life was also. Better growing medium and a little watering daily is all that was needed to keep it right.

A gardener told me a long time ago that a good cure for rust is a solution of potassium permanganate dissolved in water to make a mild concoction, then sprayed over affected plants, with repeats as needed. I have mentioned many times that simple cheap remedy for plant leaf diseases: a quarter of a teaspoon to 1 litre of water (we supply the 2.5ml spoon with the jar of Wallys potassium permanganate.)

We mentioned another cheap remedy some time ago about the problem of dry spot on lawns.

This occurs when the soil becomes too dry and will not accept water. To break the surface tension, you simply fill a watering can with warm water and squirt some dish washing liquid into the water. Give the water a stir to make it soapy and water onto the dry spots or areas. This breaks the surface tension and water can then penetrate. The same principle can be applied to gardens that have become too dry.

It is a good idea to do this about now so that when the autumn rains come the rainwater will penetrate into the soil better.

Once you have treated with the soapy water you can then use standard water and the water will soak into the soil. You do not need to supply a lot of water, instead a little water every day in either the later afternoon or early morning will do nicely. If powdery mildew is a problem, then it is better to water in the morning.

To help the control of powdery mildew simply take a heaped tablespoon of baking soda, add to 1 litre of water with a mil of Raingard and spray.

If powdery mildew is already on leaves then Spray with Wallys Super Neem Tree Oil.

I prefer to water by hand as at the same time I can then check plants for insect pests and any diseases that might be starting up and take the appropriate action to control.

It also allows me to pull out any young weeds and pick ripening fruit before the birds start pecking them. I will often come back inside with a couple of pockets full of near ripe tomatoes to go into a bowl and finish ripening.

Leaf hoppers are into many plants at this time of the year and a few nights ago I noticed a number of them on a Brugmansia I have growing in a container, so it was out with the Wallys Super Pyrethrum and a good spraying of the plant along with other plants in the area done late in the day.

Next night there was not a hopper to be seen and only the odd one has turned up since. Another spray a week or so later should be in order. For bad infestations a number of sprays may be required for a few weeks especially if they are re-infesting from other plants or from over the fence.

White butterflies are flitting around my gardens so all the cabbages and brassicas along with the tomato plants have been given a spray of Super Pyrethrum just before dusk which helps keep the caterpillars under control.

Spider mites are another pest insect that can run amok on plants at this time and a spray of wettable Sulphur powder will stop them in their tracks (do not use with other sprays including Neem tree Oil).

Lawns that have built up a layer of thatch on the soil surface can now be treated with Thatch Busta, best applied with a lawn boy for good coverage.

After application, lightly water the lawn every day to keep the thatch moist with non chlorinated water ideally.

If you are using a lawn weed killer on your lawn then you can add Thatch Busta to the mix and the dying weeds will disappear a lot quicker.

Once the lawns start to moisten up with the autumn rains you can lift some turf and inspect the soil for grass grubs and porina.

If you find a number of them close to the surface then it is the right time to kill them before they damage your lawn. Treat the lawn with Wallys Neem Powder in areas where they are to clean them up.

Two tips I learnt this week. One is soak onion skins or roughly chopped spring onions in a bucket of water. Take the water and spray over plants that snails are eating. Snail don’t attack onion plants so the onion water helps keep them off other plants. Repeat after rain.

Then you take the onion skin peelings and dry them in a low temperature oven. When dry put the brittle skins into a kitchen wiz and zap them into onion powder; it’s better than the stuff you buy.

Another tip is take the Calcium Hydroxide we talked about last week and make a slurry with it by adding a little water. You now have whitewash which you paint onto trunks of your trees in the orchard.

This is an ancient technique which creates a barrier against climbing insects, reflects harsh sunlight to prevent winter damage and naturally fights fungus diseases. It will seal and wounds in one application.

Organic protection at its finest.

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