Weeds - Control Without Chemicals
Updated: Jul 21
You don't have to use damaging chemical weed-killers. Weed-killers can damage your health and damage the environment. There are other ways to deal a deadly blow to weeds, such as manual removal of weeds, burning weeds, using weed barriers or smothering weeds. All weeds can be controlled manually, without using weed-killers, but please note that some are more difficult to get rid of than others.
Are There Weeds With Differing Degrees Of Difficulty?
Yes! Broadly, there are 3 main categories of weeds:
Annual weeds, which live only for 1 year
Ephemeral weeds, generally any short-lived plants, which live for less than 1 year
Deep-rooted perennial weeds. These tend to be more persistent and deep-rooted, and tend to be harder to get rid of. In the case of these weeds, ongoing control may be needed. Deep-rooted perennial weeds die down in winter and re-appear in spring. Note - they can re-grow from their roots if the tops are removed or burned off. Also, they can be tricky to dig out fully, and, they can grow through weed barriers over enough time.
Annual weeds and ephemeral weeds are in general the easiest to control, mainly because their roots are shallow, however, and isn't there always a however...they are very good generally at scattering their seeds around the place. Therefore, they reappear and need more controlling.
When Is The Best Time To Control Weeds?
Generally, you can control them when they become a nuisance or troublesome for you, often the spring and summer months. In addition, in late winter, or perhaps early spring, you could put weed barriers in place. Prevention is better than cure, as they say!
How to control weeds without chemicals
Avoiding pests, diseases and weeds and having good garden hygiene and encouraging natural enemies is good practice.
Manual removal and cutting back
Weeding by hand: You can pull up annual weeds by hand before they set seed. Perennial weeds should be dug out with as much root or bulb as you can.
Weed-burner: You can scorch weeds between paving slabs and on block-paved driveways by blasting them with a flame gun. It is best to do this when the foliage is dry, and make sure to allow plenty of burn-time for deep-rooted weeds.
Garden Hoe: Run a hoe over the patch of ground in question to kill most weed seedlings. It is better to do this on a dry day with little to no wind, so that seedlings dry out on the surface rather than re-rooting in moist soil.
Weed knife: A weed knife is a useful for weeding between paving slabs and by path edges.
Repeated cutting: In large weeded areas, repeated cutting with a strimmer, to ground level, over several years, will weaken and can kill some weeds.
Root barriers: root barriers can be inserted into soil to stop perennial weeds spreading into neighbouring areas or gardens. You can also use them to restrict invasive plants such as bamboos. For flexibility, use a tough fabric root barrier.
Mulching: You can use organic mulches such as bark or wood chip to smother weeds around plants. Top them up to a minimum depth of about 4 to 6 inches to smother established weeds, keeping woody stems clear of mulch to prevent rotting.
Edging boards or strips: These can be used to edge lawns and prevent unwanted grass growing into the border.
These fabrics can be laid over soil which you have recently cleared to suppress re-growth of old weeds and prevent new weeds from becoming established. There are many types of fabrics available.
Woven materials: These are sheets of woven plastic. They are available in different grades which vary in toughness, durability and weight. You do not need to cover this fabric with mulch. However, woven materials tend to be heavier than spun materials and cut edges can fray!
Spun materials: Usually manufactured from plastic fibres bonded together forming a sheet, and can be used in most situations, short and long term, but it is best to cover this fabric with a protective mulch. Spun materials tend to be lightweight and easy to cut, they don’t fray along cut edges, are very porous, allowing water to reach plant roots. However, many of the cheaper versions don't last too long and the tougher ones can be a little pricey.
Biodegradable mulch film: A compostable black plastic mulch. As it is biodegradable, it naturally degrades in or on the soil, and is effective against annual weeds, but it is probably best to use heavier grades to suppress perennial weeds. The more fragile, lightweight grades degrade in about 2 to 4 months, but heavier grades are less prone to damage.
Paper mulch and carboard: Suitable for short term weed suppression. On the plus side, it is biodegradable, made from renewable resources and paper mulches are light and easy to apply. You can re-use cardboard from packaging to mulch paths and beds. However, paper mulches degrade quickly where they touch the soil, and cardboard needs to be weighted down with bark or compost to prevent it being blown away. As it degrades quickly, it will need to be replaced often.
Plastic sheeting: You can use plastic sheeting to suppress weeds as a short term unsightly solution in areas of the garden where you are less concerned about appearance. On the plus side, it is cheap and it is easy to cut with a knife or scissors. However, it is impermeable to water, so the ground can dry out underneath the sheeting, and the rain will gather on the surface - if you make holes in the sheeting it will allow water to penetrate, but can provide an opportunity for weeds to grow!
Repeating some of the steps above each year is likely to be needed. This is not a one-off task! If you need any assistance with your weeding requirements, we at SJ Wilding are happy to get your weeds under control.