For gardeners, life without weeds is a utopia. You want what you plant to remain what is planted until the time of harvest. Unfortunately, weeds have other ideas. And because they are so prolific when it comes to growth, they can take over the garden if left to flourish.
Weeds are so persistent and ubiquitous that questions like, Can you spray weed killer in a vegetable garden? are very common especially among newbie gardeners. Left alone, weeds suck the life out of edible plants in a garden by efficiently using up the soil nutrients leaving other plants with little or nothing.
So controlling or killing weeds in a vegetable garden is very important. And one of the easiest ways is via spraying weed killers in the garden. But as you would find out, taking care of a weed problem like this is not so straightforward.
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Can You Spray Weed Killer in A Vegetable Garden?
When it comes to using chemical sprays to kill weeds in the garden, there are many options available to gardeners. So yes, you can spray weed killers in a vegetable garden.
The real issue though is the type of weed killer used. And that depends on factors such as whether the garden is exclusively organic, the types of vegetables, and how long you want to start planting after spraying the weed killer.
All the vital issues would be looked at so you get a pretty good idea of what you are up against while trying to eradicate weeds in your vegetable garden.
Vegetable Garden Weed Control
For vegetable gardens, weed-killing options using chemical sprays are limited to just a few choices. These include
Preemergence herbicides – These are usually applied directly on the soil before planting begins to prevent the growth of the weeds. In some cases though, they can be applied immediately after planting the vegetable seeds or plants but before the weeds germinate.
Postemergence herbicides – As the name implies, they are used to kill weeds that have passed the seedling phase and are now weed plants above the soil. The chemicals kill the weeds when they come into contact with the leaves, stems, or root system after traveling down to the roots.
These are the two broad categories for weed killers. The herbicides are further sub-divided into their mode of action. These include:
Selective herbicides – These only destroy weeds sparing all beneficial plants in the garden. They are excellent if the plan is to eradicate weeds such as thistles and dandelions.
Non-selective herbicides – These would eradicate all plants they come into contact with. They are great for gardens that have no vegetables. For instance, you could use them to help clear all the plants, including weeds, in a garden as a prelude for getting the garden ready for planting.
And finally, weed killers can be grouped according to how they live/move within the plants after application.
Contact herbicides – These are normally used for annual weeds. The chemicals kill only the parts of the weeds they come into contact with such as the leaves and stems.
Systemic herbicides – Perfect for perennial weeds, they are absorbed right down to the roots after application. They destroy the whole plant from the leaves to the root system. Due to their mode of action, it takes several days and sometimes weeks to see results.
From the above, it is clear no single herbicide would be effective against all weeds especially in a garden with mixed vegetables. And because some vegetables are sensitive to the chemicals, using them might cause you a lot of grief.
So before using any synthetic weed killer, you need to read the product label very well. Most labels have a listing of the vegetables the chemicals are safe to use for including the mode and frequency of application.
Below are some of the active ingredients in synthetic weed killers and their mode of action.
Trifluralin – Many brand names use this chemical as an active ingredient. It is a preemergence herbicide formulated for controlling grass problems in gardens.
Glyphosphate – Glyphosphate-based herbicides are formulated for controlling preexisting weeds in gardens. This is the most popular, non-selective brand of weed killer recommended for limited application in a vegetable garden.
Dachthal – Several brands of inorganic weed killers based on this chemical are available in stores. They are selective, preemergence herbicides perfect for controlling broadleaf weeds and grasses while protecting beneficial vegetables.
Poast herbicide – Herbicides formulated with this chemical are best for controlling existing weeds in the garden. Because they are non-selective, it is best to use them before planting or before the vegetable seedlings emerge from the ground.
Problems of Using Synthetic Weed killers
No matter how careful you are, the chances of encountering problems with chemical sprays are high. For instance, the wind can blow the herbicide onto your vegetable plants. In extreme cases, that would kill your vegetable. At the least, the introduced chemicals would undermine the whole idea of producing chemically-free, non-toxic organic food in the garden.
There is also the issue of how long the chemicals remain in the soil. Herbicides are usually designed to degrade over time. But the rate of degradation is still dependent on factors such as light, moisture level, and temperature.
The presence of the residual chemicals in the soil have been known to impact negatively on children and pets and even the vegetables when traces of the chemicals are absorbed.
Fortunately, the impact of residual chemicals from herbicides is very limited due to the strict regulations on the production of garden herbicides.
To be on the safe side, it is recommended you buy from only reputable stores, read the labels carefully, and adhere to the instructions on the labels.
Tips for Using Chemical Weed Spray In A Garden
- Identify and study the type of weed to be killed before buying the herbicide.
- Familiarize yourself with the current regulations on the use of herbicides. You might need a permit to use some products.
- Cover your vegetables as much as possible to protect them from chemicals drifting in the wind while spraying.
You should also cover troughs, pans, water tanks, etc., lying around in the garden. Remove them if possible before you start.
- Ensure you follow all safety precautions on the label to protect yourself and others. Wearing protective clothing is important.
- Always store herbicide in the containers you bought them in a properly marked cabinet far away from food sources. Also, it is not advisable to store different herbicides close together to avoid cross-contamination.
- Bath and wash clothes thoroughly after spraying the herbicide. If you can’t launder the clothes immediately, keep them in a safe place away from other clothes. Wash them separately from other clothes.
Homemade Weed Killer Safe for Vegetable Garden
There are several organic ways to control weeds in a garden without spraying. But if spraying is your preferred choice, a few workable options are available to you including some homemade remedies.
For instance, there are several citrus-based organic weed killers that are very safe to use. These postemergence weed killers are very effective for eradicating young weeds taking about an hour or less to do the job.
Other organic products are based on:
Vinegar or acetic acid – The active ingredient in regular household vinegar is acetic acid. So in a way, you could say acetic acid is the stronger version of vinegar.
Both can be used to kill weeds with acetic acid acting faster than vinegar. For young and tender weeds, spraying vinegar should be enough to kill the weeds; while stubborn, old weed plants would be better dealt with using acetic acid.
There are several resources online on how to make an effective, homemade garden weed killer using vinegar. You’d be pleasantly surprised how easy and cost-effective the process is.
Eugenol compounds – Like vinegar or acetic acid, Eugenol-based compounds kill weeds that are above the ground while sparing the root system. They are derived from clove essential oil, a vital ingredient found in most organic weed Killers.
Salt – Some weed killers use ordinary salt as the main ingredient. When applied to the soil, the salt dries up the moisture and removes the nutrients inevitably killing the weeds.
However, salt-based compounds are not widely used because they can also affect the whole garden if applied extensively. The best place to apply them is along the edge of the fence around the garden and other places where crops won’t be planted.
This list is not exhaustive. A bit of online research or asking a neighbor would reveal a trove of information you’d find useful for organic weed control.
And as in the case of herbicides, ensure you read the labels carefully to know the exact ingredients, instructions, and other useful information related to how to apply and use the compounds.
For new gardeners wishing to grow food crops, weeds can kill any enthusiasm they had. This can result in abandoning the garden before harvest. It’s therefore really important to have a weed control strategy handy because weeds in a vegetable garden are as inevitable as sunrise and sunset.
Spraying a weed killer in a vegetable garden is one of the simplest and fastest methods of taking care of the problem. But it comes with many downsides especially if herbicides are used. For people bent on organic gardening, a variety of organic options for controlling weeds via spraying are available to them.
That said, gardeners are strongly advised to, among other things, read the labels on the product they want to use to get it right. Asking experts or veterans who have been down this route before for advice would be a very smart move too.