Weeding is one of the least popular jobs to be done in a vegetable garden. If the weather is fine and there is time to spare then it can be quite enjoyable. However, during busy periods weeds can quickly take hold and controlling them feels like more of a battle than a leisure activity. So, what are the best ways to keep weeds under control without resorting to harmful methods such as weedkillers?
Prevention is Better than Cure
The first rule when considering weed control is to minimise the amount of work. Use the following methods to stop weeds growing in the first place:
- Exclude light from unplanted vegetable beds. Placing sheets of cardboard, weighed down with bricks, over a vegetable bed before planting will ensure that weeds don't get the light they need to grow. There will still be some persistent perennial weeds that survive such as horsetail (mare's tail) but the problem will be much reduced.
- Add Mulch. Once plants have grown beyond the seedling stage and are established, you can add mulch to suppress weeds, retain moisture and feed the plants. See our Mulching article for details.
- Consider using deeper beds: Deeper beds (often raised beds with sides of 30cm or 12 inches filled with high-quality compost mixture) give plants more room for their roots to extend downward. This means you can usually space plants closer with less space for weeds in-between. Many low-maintenance systems such as Square Foot Gardening use this concept combined with sterilised weed-free soil on top.
- Grow the Weeds First: If you are using home-produced compost then it often contains weed seeds (if the compost pile didn't get hot enough to kill them). When preparing a vegetable bed with compost I will sometimes water it for a few weeks to encourage the weed seeds to germinate. They can then be sliced off using a hoe or their roots disturbed using a garden hand-fork a week before I put in the plants I want to keep. This method can be a great time-saver because it is much easier to weed a bed when everything in it is weeds and you are then left with almost weed-free soil. Just ensure you don't disturb the soil too much as that can bring fresh weed seeds to the surface. Unfortunately it doesn't work so well in areas where weed seeds are being blown in from neighbouring fields or gardens.
The Seedling Stage
This is the most important stage because weeds compete with young seedlings for water and nutrients. Weeding by hand is often necessary because small seedlings have shallow root systems which can be easily damaged. It is important to weed carefully round young plants to ensure that the roots remain undisturbed at this critical stage in their growth. If you are thinning out plants that are close together then it can be better to cut unwanted seedlings off at the base as pulling them up can disturb the plant you want to keep.
Weeding is the primary reason I grow most vegetables in rows because it helps me to spot what is a weed and what is a seedling I want to keep. To make this even easier it is often worth marking the row after sowing the seed by using string between two stakes or adding a small line of darker commercial compost on top.
An alternative solution is to raise many of your plants in pots and trays of sterilised soil whilst leaving the vegetable beds covered. Raising more plants in pots does require more vigilance but can be less effort than lots of meticulous hand weeding.
The Right Tool for the Job
Weeding between mature plants is easier because there is less risk of damage to their root systems. At this stage I like to use a hoe to slice off the weeds just below the surface of the soil. When I first started gardening it was a while before I realised that a hoe is essentially a knife on a stick and not for churning up the soil! Because of this hoes should be light to use and their blade should be kept sharp. As most hoes are sold very blunt this will often involve sharpening the tool using a grinding machine (best done by someone with the right equipment and experience). Once this has been done properly it can be kept sharp by hand using a whetstone. Professional gardeners sometimes talk about 'keeping the soil moving' as the best method of weed control and a good hoe is perfect for doing that.
Which hoe to use is a very personal choice. I personally love the Wilkinson Sword Swoe which is light and easy to manoeuvre around plants but there are many other choices available. For deep-rooted weeds you need a tool that can lever out as much of the root as possible. My new-found favourite is the Cobra-head weeder which is a great all-purpose tool for hand weeding but I will often use a standard garden hand-fork too.
Once plants approach harvest the weeding eases off. Because your plants are now well established you can usually let the weeds coexist with them as they will be much smaller. Just make sure that the weeds don't grow too large and produce seeds - there is a lot of wisdom in the saying "One year's seeding makes seven years' weeding"!
Weeds can in fact be very useful over winter. They prevent bare soil being exposed to the elements which can cause erosion and loss of nutrients from water run-off. Many weeds also do a good job of bringing nutrients up to the surface and can be dug in or added to the compost heap in the same way as a green manure (cover crop).
Of course, there are many other ways to speed up weeding and I have just mentioned my favourite methods. If you have tips or ideas to share then please do add them as a comment below.