For Nathan James Dodd eradicating garden weeds seems like an endless task, but a necessary one that needs to be done in the most efficient way with least harm to the environment.
We regularly provide advice on this subject and here are your most frequently asked questions:
How Do Systemic Weedkillers Work?
After applying systemic weedkiller to the plant's leaves, it travels through the plant and into the roots. Although slower to take effect than contact weedkillers, a systemic weedkiller works by restricting the plant's ability to transport water and nutrients until the plant dies.
What Is A Contact Weedkiller?
Contact weedkillers only kill the parts of the plant they come into contact with, ie the leaves and stem above ground level. You may have to re-apply several times, as the weedkiller won't penetrate the plant's roots.
Which Weedkiller Should I Choose?
Systemic weedkillers will kill most weeds but are best used to eliminate perennial weeds with long roots such as dandelions. Contact weedkillers are excellent to deal with annual weeds.
What Is A Selective Weedkiller?
Selective weedkillers are formulated to kill only particular weeds, mostly broadleaf which are often shaped like rosettes and found in lawns.
And Non-Selective Weedkillers?
These are also called 'broad spectrum' herbicides and kill practically every plant they come into contact with.
Where Do I Use These Weedkillers?
Selective weedkillers are most useful on lawns as they will kill broadleaf weeds but do not affect the grass. Use non-selective weedkillers on large areas that need to be cleared, drives and paths.
Is There An Organic Alternative?
Until recently commercially produced organic weedkillers have been thin on the ground. DIY weedkillers such as distilled vinegar with a high acid content is a non-selective contact herbicide that will kill small sized annual weeds and perennial seedlings. Rock salt can be used to dehydrate the leaves and roots of a plant but it's residual i.e. will remain in the soil and this isn't a good idea if used where you intend to plant in the future. So it's best on paths, block paving or similar only.
Weed Control Fabric suppresses weed growth but allows water and nutrients to pass through and we are now beginning to see new products on the market from well known companies that can be classed as organic. Bayer has introduced a 'Natria' range that includes a Super Fast Weedkiller that uses fatty acids to disrupt the cellular structure of the plant, causing them to dehydrate and die. It's ideal for eradicating annual weeds and can be used around vegetables.
With multi-national companies now entering the market with their financial and research muscle, there's no doubt that better and more effective 'natural' weedkillers will be introduced. Time will tell whether they are proven to be effective and if the organic market is large enough to sustain a large range of such products.