Its been a hot summer. By November last year, temperatures were exceeding 30⁰C in many areas, and it can only get hotter as we enter the hottest months of summer.
To curb the higher demand for water there’s likely to be water restrictions and an overload of pests which breed exponentially in hot, dry weather. All of this puts plants, and especially vegetables, under huge stress.
Don’t skimp on plant nutrition
Healthy plants that receive the necessary nutrients through regular fertilising, are more able to withstand such stress, says Marlaen Straathof from Kirchhoffs Seeds.
They develop strong root systems to go in search of water and an abundance of leaves to convert sunlight, water, and carbon dioxide into food through photosynthesis.
A monthly liquid drench like Margaret Roberts Organic Supercharger is especially beneficial for vegetables and bedding plants. It contains both macro and micronutrients. Because it is diluted there is no danger of it burning the roots.
For shrubs, roses, perennials and the lawn, as well as vegetables, the easiest way to top up nutrition is with an organic granular fertiliser. However, the fertiliser needs to be watered in well after application so that it doesn’t burn the roots.
Rose grower Ludwig Taschner recommends a once a month application of Vigorosa 5:1:5 (25). In addition to all the essential nutrients, it contains humic acid which ensures that the roots are easily able to absorb the nutrients once they are dissolved in water from rain or irrigation.
Humic acid is also a powerful stimulant of beneficial fungi that are essential for soil health and it is high in carbon which is the life blood of good soil.
Use water wisely
Water is always the big issue but the good news is that gardens can survive with grey water.
This is water from the bath or shower, and from the washing machine and dishwasher, provided that eco-friendly detergents are used and that the oil is rinsed off before stacking the dishwasher.
It is surprising how much water can be saved from a shower. Keep buckets and tubs in the shower. During Day Zero in the Western Cape, householders would stand and shower in a plastic bowl and use that water on the garden.
Other strategies that you can use:
- Cover garden beds with a light 2cm deep mulch. This keeps the soil and roots cool, prevents weeds and reduces evaporation from the soil.
- For shrubs and roses, place a plastic two or five-litre cool drink bottle cap side down (without cap) at root level next to the plant. Cut off the base of the bottle. To water, fill the bottle and the water will go directly to the roots.
- Use a handheld hose or watering can to water around the base of the plants rather than using a sprinkler. This minimizes the waste or water and loss of water through evaporation.
- Water early in the morning or early evening after the heat of the day.
Eradicate pests
Aphids, white fly, and red spider all suck food and moisture out of the leaves while leaf eating beetles and caterpillars destroy the leaf cover. Ants are also a menace as they support aphid populations and carry viruses. All this weakens the plants and puts them under stress.
January and February are peak pest months because conditions are ideal for breeding, and pests can multiply fast because they have a short breeding cycle.
The key to good pest management is early detection. This doesn’t mean dousing the garden with poisonous chemicals. There are plenty of organic or biological alternatives.
- Ludwig’s Insect Spray Plus contains garlic, canola oil and pyrethrum and is particularly effective against aphids, red spider mite, whitefly and flower beetles. There is no secondary poisoning to birds, ladybirds, earthworms, bees, chameleons and lizards. Vegetables or fruit can be eaten 24hours after spraying.
The dosage rate is 100 ml in 10 litres of water but for red spider this needs to be increased to 200 ml in 10 litres of water. Spraying the plant and the soil around the base of the plant needs to be repeated weekly until the infestation has gone.
- Margaret Roberts Organic Insecticide is safe for using near fishponds, as it is not toxic towards fish. This spray will control most small-bodied insects in the garden but will not harm natural predators. It can safely be used on edibles, including herbs, which can be harvested 24 hours after application.
For caterpillars there is Margaret Roberts Biological Caterpillar Insecticide. Spray on the foliage of plants and around the plant when larvae of caterpillar species are small and feeding actively. Bacterium enters stomach of larvae and it stops feeding within hours and die within a day or two. It is harmless to humans, pets, birds, beneficial insects and wildlife. Edible crops can be harvested directly after last application.
Provide shade
Protect tender leafy veggies, seedlings or newly planted beds from harsh sun with 30% to 60 % shade cloth. Make a temporary structure by pushing poles into each corner of the bed and draping the shade cloth over the poles. Make sure it doesn’t touch the plants.
Control fungus diseases
Cloudy, cooler rainy weather alternated with warm to very hot days create conditions that are favourable for many plant diseases. Tomatoes and many other vegetables are susceptible to diseases like bacterial spot, botrytis rot, black spot and downy mildew.
Healthy plants can be protected with weekly applications of Copper Count-N. You can harvest your tomatoes 3 days after applications. Copper Count-N is a broad spectrum fungicide and bactericide for use in the garden to control almost all known diseases you can possibly find in your garden.
For more information, visit Kirchhoffs
TEXT: Alice Coetzee
