Weed control made easy
Weed control made easy may sound too good to be true!
But in this blog I want to take a look at main options available to the gardener when faced with the inevitable flush of weeds that grow each spring.
Spoilt for choice?
When you walk into a garden centre or DIY store you are faced by masses of bottles of garden weed killers.
I don’t know about you but this has me scratching my head and I’ve been in the garden industry for over 50 years!
The brand names often stay the same and are familiar but the active ingredients and the use to which they can be put sometimes changes.
I find that you really know which garden weed killer to use and which is the right weed control for you!
With this in mind in this blog I want to try to unravel some of those mysteries.
And hopefully help you to make the right choices to improve your control of weeds!
Non chemical alternatives
Of course you may prefer not to use chemicals. I’m pleased to see that increasingly more gardeners are looking at the non chemical approach.
So perhaps black sheeting laid on the soil for months is for you.
To get on top of really tough and persistent weeds [ground elder, bindweed, etc.] this is probably still the best means of control.
It works by excluding the light for several seasons or even years. This will eventually exhaust the reserves of ground elder, couch grass and bindweed. But naturally in the meantime it limits what you might be able to grow there.
Cover the soil with plants!
A great way of controlling weeds is to cover the soil with ground covering plants.
This works especially well if annual weeds are the problem.
Persistent perennial weeds may not be deterred by covering your borders with ground cover plants.
I find that weeds such as thistles, nettles, docks, bindweed and couch grass will not be tamed with ground covering plants!
I’ve written about using ground cover plants in this blog here and I hope that you find it inspiring and useful.
I know that there are fans of flame guns for weed control. I use one occasionally myself.
But to claim that this is a non chemical weed control method is misleading. I’ve even heard some claim that this is an organic method of weed control. Let’s not forget that it relies on burning gas, paraffin or other fossil based fuels.
A quick pass over a patch of weeds is an effective way of clearing a flush of annual weed seedlings.
The flame should not actually cause the weed to catch fire but it should ‘cook’ it. You see the flame should heat up the plant cells so that they subsequently collapse.
A flame gun can be useful if you’re trying to create a ‘stale seedbed’. That’s where you allow weeds to germinate and then kill them without disturbing the soil.
Do remember that every time you disturb the soil you will be bring more weed seeds to the surface where they will germinate.
Read up about stale seedbeds here.
Digging and hoeing
Digging your patch and removing every bit of weed root can be very effective if tiresome! Miss a bit of couch grass or bindweed root and it grows back!
For annual weeds regular hoeing works well.That’s because they lack significant food storage organs.
Many perennial weeds have these and it enables them to rapidly bounce back.
You’ll need to dig your plot but also fork through the soil to find every bit of couch, creeping thistle and bindweed.
But for most gardeners chemical weed control using weedkillers is still the preferred means of control.
And so I’m back to those garden centre shelves again!
Weed control made easy with chemicals
These man-made garden weedkillers can be divided into groups and it is worth understanding them.
Contact garden weed killer
As their name implies these need to make actual contact with a weed.
They need to hit a piece of green plant tissue to work.
It’s claimed that they have little effect beyond that.
So for tidying up an area that is covered with annual weeds, contact weedkillers might be best.
They will control chickweed, groundsel, hairy bitter cress, shepherd’s purse, sow thistle and lots of others.
It’s claimed that spray that hits bare soil is broken down and quickly becomes inactive.
As a consequence you have to hit the green leaves of a weed to kill them!
The most widely used weedkiller in this group is called Scotts Weedol.
However there are increasingly alternatives to this based on plant extracts. Pelargonic acid herbicide is one that shows promising results.
Translocated garden weed killer
Translocated weed killers travel throughout the plant’s vascular system and even get down into the roots.
These are very useful for killing very tough weeds.
Where you have a mix of annual weeds but, more importantly, a lot of persistent perennial weeds you do need something stronger! This is where the translocated weedkiller comes into its own.
Once again, there needs to be plenty of top growth to absorb the spray. These sprays go in through green leaf and shoots.
Be aware that they often take longer to show any effect than the contact sprays. This is because they are going right down into the root system to kill even them.
Scotts Roundup is perhaps the most widely used one but Westland Resolva24h is worth considering. This product has an added ingredient that shows up within 24 hours so that you can quickly see any bits that you have missed!
Importantly, the weedkillers in this group are generally not selective. So that means that if you spray it and it’s green it will be harmed by the weedkiller.
Do spray with care among plants that you want to keep!
Beware that Roundup is based on glyphosate which is likely to be phased out soon. There is already a Roundup spray that has no glyphosate in it! That’s what I mean about the ingredients changing!
Selective garden weed killer
Also translocated types, these but can be effective at killing one group of plants but not another.
So for instance lawn weedkillers fall into this category since they kill most broad leaf weeds but do not harm grasses.
Selective weedkillers are also translocated but importantly they don’t kill everything they touch that is green!
So in this group we have those weedkillers that you can spray on your lawn to kill daisies, speedwell, clover and dandelions. But importantly they leave your grass unharmed!
A popular example would be Scotts Weedol Lawn Weedkiller.
Another often used selective weedkiller is Vitax SBK Brushwood Killer. This is a much stronger product and can be used to kill nettles, brambles, ivy and other woody plants.
Just like the lawn weedkillers, SBK has no effect on grass.
Residual garden weed killer
The last major group is the residual garden weedkillers.
These may have some contact, translocation and selective garden weedkillers in them. But the prime ingredient is an ingredient that will go on controlling weeds long after you have sprayed it.
They form a barrier on the surface of the soil. This kills seedling weeds as they try to grow through it. This will primarily control annual weeds but may also check stronger growing perennial weeds too.
A residual garden weed killer would be used on paths, drives and areas where you don’t intend to grow any plants for a while.
Eventually the effect wears off but, depending on their ingredients and the strength that you apply it, they can give effective weed control for half a year or so.
Once applied, it is important to leave the surface undisturbed otherwise that barrier will be broken.
Once again, it is a Scotts product that you will most often see and this time called Weedol Pathclear. Other manufacturers make similar residual weedkillers.
Chemicals not sprayed
There are a few products that are not sprayed onto weeds.
Those formulated as granules that can be scattered on weeds tend to be only for professionals.
However I’ve found that those formulated with gel are well worth considering.
This is especially so to control bindweed and other difficult to control weeds.
The gel enables you to apply the weed killer directly onto the weed’s leaves where it stays much longer being absorbed.
Check the detail!
Finally, I must stress just how important it is to read the small print. It’s also vital that you following the instructions on the pack.
You should find that staff at well run garden centres will be knowledgeable and be able to guide your choice.
Any surplus spray and empty containers should be disposed of according to the instructions printed on the pack. You may find that your local authority will accept empty chemical containers.
If garden weedkillers are not for you but you would still like to use them; you may be able to get these applied for you. They may also have more effective commercial weedkillers. Application needs to be done by a suitable qualified garden contractor.
Whether you do this or not, I hope that now you will approach those shelves of weedkillers in garden centres armed with a bit more understanding.
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