The backyard vegetable garden is a lot like a farm in that they are both optimised for production. When starting a veggie garden the first action that people take is to clear the area of any grass or plants that could compete with the planted vegetables. This cleared area is also often away from the rest of the garden so its not in the shade and gets plenty of sunlight.
While this garden design minimises the competition faced by vegetable plants for nutrients, water, light and thereby maximising their growth, it does have it’s drawbacks. Removing and isolating the veggie garden from a diversity of plants (such as your lavender, bottle brush and roses) can discourage beneficial insects from visiting.
Many insects in the hymenopteran family (wasps) feed either on garden insect pests or destroy the eggs of pest species through parasitism. This can be a great benefit in controlling the amount of common garden pests such as caterpillars or aphids. However, most of these wasps at some point in their life cycle require nectar and pollen, the very resources that were removed when you cleared those other plants for your garden! In this respect a veggie garden would be better off being within the rest of the garden plants, least surrounded by flowers or even inter-planted with ornamental plants.
Studies on farms and plantations have had success in increasing beneficial wasp numbers by adding flowering plants between crop rows. Typically the flower alyssum was used in these studies (which can make a nice hedge around gardens) due to its prolific flowering, however any flower may have this affect.
So having flowers near to a garden year round can keep these beneficial wasps in higher numbers year round. Additionally, a constant supply of flowers can also be attractive to pollinators such as bees and many flies, while leaf litter dropped by ornamental plants can be attractive to decomposing insects like worms which breakdown the leaf litter and help aerate the soil.
These factors combined mean that some flowering plants around your veggie garden can reduce the amount of pesticides and work needed and hopefully get you that extra harvest.
So next time you plan a garden, literally think out of the box and consider planting your vegetables in unorthodox locations such as basil around your lavender or oregano as a ground-cover beneath your wattles.
If you don’t have room or otherwise cant plant flowers you could always try providing insects with artificial nectar honey solution, the recipe my lab uses is as follows:
- 180ml Honey
- 1800ml Hot water
- 10.8g Ascorbic acid
- 1.8g Sorbic acid
- 1.8g Paraben
- 10ml 70% Ethanol
Dissolve the Sorbic acid and Paraben in the Ethanol.
Dissolve the Honey in the Hot water and allow to cool.
Add the Ascorbic acid to the honey and water and mix well.
Add the dissolved sorbic acid and paraben and mix well.
Store at -4oC.
Let me know if you try this!