How to combat weeds in your vegetable garden

Weeds are plants in the wrong place and so are unwanted. If plants other than your vegetables are growing in your vegetable patch, they could be ‘stealing’ nutrients, or water, or light, or space, or all of those from your vegetables. They might also be reservoirs of pests and/or disease that would affect your vegetables. The weeds are then unwanted.

Weeds are often, what is known as early colonisers, that is they are quick to germinate, fast to grow and spread. So, they will take advantage of the good soil, and available space, in a vegetable patch where you have cleared the soil for sowing seeds or planting seedlings. Many will not only spread by seed but can spread vegetatively using stolons (creeping stems) or rhizomes (creeping roots) that sprout new plants from stem or root nodes.

An additional challenge to keeping your vegetable patch clear of weeds is that you do not want to damage or contaminate the vegetables you are going to eat.

How to Keep Your Vegetable Patch Clear of Weeds

Put the Effort in Early

Take the time to make sure you clear all the weeds, including their roots from the vegetable patch when you are preparing it for sowing or planting. Dig over the soil of your empty vegetable plot and remove all root fragments. A garden sieve will help filter out the roots and will also improve the tilth of the soil.

Some safe organic herbicides are registered for use in vegetable plots, and these can be used to kill young weeds that might emerge from any seeds in the soil; after clearing the soil and sieving leave the patch for 2-3 weeks and wait to see what seeds germinate. Spray the seedlings with the natural herbicide. Such fatty acid type herbicides will not affect the soil or the vegetables you will be planting.

Weed Suppressing Mulch

A thick layer (5-10 cm) of well-rotted compost or other organic material can help suppress weeds. Make sure the material is not a potential source of weeds seeds or fragments. A mulch layer can be very efficient around more mature vegetables, but it might make planting seeds or seedlings difficult as a trench will need to be made in the mulch to expose the soil below for the young plants.

Regularly Tend Your Vegetable Patch

Weeds are always easiest to get rid of when they are young and small. Young weeds can be easily manually removed, but you will need to be able to distinguish them from your vegetable seedlings. So, when you are planting or sowing your vegetables, make sure to mark their position. You do not want to accidentally dig out your vegetables thinking they are weeds.

Natural herbicides such as those with fatty acids that are registered for use in vegetable patches can be used to carefully spray the weeds, but care must be taken to apply in such a way that the herbicide will not drift onto the vegetables, as it will burn the vegetable foliage.

If the Weeds Get Out of Hand

Perhaps you have gone away on holiday for 2-3 weeks, and on your return the rapid growth of weeds has taken over your vegetable patch. If the weeds have developed large roots, manual removal may be more difficult, and it may damage the vegetables. Identify the weeds and determine the best solution for safe removal. Some, such as convolvulus may be best cut down and then the roots covered with black plastic to stop light getting to the weed roots, or the cut stem immediately painted with an approve systemic herbicide gel to kill the roots.

Keeping weeds out of your vegetable patch will help you grow the most healthy and productive vegetables, because they will have all the nutrients, water, light, and space they need. And pests and disease will not be hiding in the weeds ready to infest or infect your vegetables.