By: Susan Patterson, Master Gardener
Sometimes we gardeners are sure that the weeds are going to get the better of us. They test our patience to the very core, sneaking up where they don’t belong and creeping in where they are hard to pull. While there are many different chemical sprays to combat weeds, some of these can be quite dangerous and costly. For this reason, some of us may consider using salt to kill weeds. Let’s learn more about killing weeds with salt.
Although killing weeds with salt may seem strange, it is effective when used cautiously. Salt is inexpensive and readily available. Salt dehydrates plants and disrupts the internal water balance of plant cells.
Salt is best used for small-scale gardening where it will be easily diluted by rain or watering, however. If salt is used on a large scale, it can create soil conditions that are not suitable for growing plants for quite some time.
Making a salt weed killer mixture at home is not difficult. You can add rock or table salt to water until it dissolves. Make a fairly weak mixture to start with – 3:1 ratio of water to salt. You can increase the amount of salt daily until the salt begins to kills the target plant.
Adding a little bit of dish soap and white vinegar helps with weed killing effectiveness. It lowers the surface tension of the water, which allows the salt solution to be absorbed by the plant.
Applying salt to weeds must be done extremely carefully to avoid damage to nearby vegetation. Use a funnel to direct the saltwater to the weed; this will help keep the solution from splattering.
Once you have applied the solution, water any nearby plants well. This will help to mitigate damage and will cause the salt to leach below the root zone of the plants.
Caution: A popular question asked by gardeners is “Can I pour salt on the ground to kill weeds?” This is not a good practice, as it can easily damage surrounding vegetation and soil. The salt weed killing method works best if the salt is diluted and applied directly to the weed. Always use caution when working with salt – do not ingest the salt or rub it in your eyes.
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Read more about Organic Gardens
Say goodbye to those garden weeds for good.
As gardeners start heading outside this spring to tidy up flowers and plant new ones, it's important to think about how to safely dispose of weeds without the use of harmful chemicals.
Common household supplies are brilliant for getting rid of nasty garden weeds. Whether you only have 10 minutes, or a whole afternoon to kill weeds, cheap and highly effective items found at home can work wonders. From salt to boiling water, vinegar and even baking soda, these cheap and cheerful quick tips are brilliant for even the most time-strapped gardeners.
The gardening experts at BillyOh.com have suggested the best chemical-free plant-friendly weed killers everyone can make in the comfort of their own home — and they're items we all have sitting in our kitchen already.
Vinegar may not be the first thing you think of when it comes to safely getting rid of weeds, but it will kill everything it touches. It's worth knowing that it won’t work on deep rooted perennials and may just ‘burn’ the visible parts of the weed, but it's great to use if you want a quick fix for removing any visible weeds poking out.
Vinegar is highly effective on small weeds, but it can also alter your soil to prevent things from growing there in the future, so it’s best to use this on block paving and gravel driveways only. Simply add it to a sprayer and squirt onto the leaves and stems of weeds.
Salt has been used as a herbicide and pesticide for hundreds of years and can be very effective to kill off those nasty garden weeds. Dilute three parts salt with one-part water, mix and leave to stand for 10 minutes to make sure the salt has dissolved. Spray the weeds with the salty solution, but make sure not to use it on lawns or flowers as it can prevent future growth. It's a simple and cost-effective way to keep the weeds at bay.
3. Boiling water
Boiling hot water can destroy growing weeds very quickly (and easily). Top tip: take care when pouring the boiling water not to damage any nearby flowers or plants, so only pour small, controlled amounts to avoid the water splashing.
4. Baking soda
A brilliant tip is to use baking soda on pesky weeds — something most Brits will find in the kitchen cabinet. It's great to put on the weeds growing in concrete cracks (such as patio slabs) to avoid killing healthy grass, flowers and other vegetation.
Another great chemical-free weed killer is mulch, which is best layered with newspapers or cardboard to eliminate existing weeds. Wonderfully, too, it will also stop the next generation of weeds from growing.
Cornmeal gluten (ground from dried maize) acts as an organic herbicide and is free of toxic chemicals, which is great news for your garden. Scatter cornmeal over soil to prevent crabgrass and dandelions from growing.
7. Rubbing alcohol
Another excellent and efficient way to banish weeds in your garden for good is by using alcohol. Mix two tablespoons of rubbing alcohol with a litre of water, and then pour the mixture into a spray bottle. The alcohol will remove the moisture that weeds need to survive.
There are many ways to kill grass and weeds. Killing them permanently, however is quite difficult. To kill any kind of grass or weed permanently you need to attack and kill the plant’s roots.
If you are trying to kill a large area of vegetation an easy way to start is covering the area with cardboard or wet newspaper to smother it. Depriving the grass and weeds of light and fresh air will kill the plants and make it easier to dig up their roots.
There are lots of natural weed killers that you can use. One popular recipe involves the use of Epsom salt, dish soap, and vinegar. However, the response to this particular recipe is not always positive.
Lucky for you, that’s not the only recipe for DIY weed killer. Here’s an article we’ve penned on how you can make some eco-friendly weed killers. Or if you’d prefer to just buy some natural products, here’s a review of Pulverize natural weed killer.
Salt will kill anything that grows … but that doesn’t mean it’s a good herbicide! Source: mzayat.com & fortcollinsnursery.com
Actually, this is both true and a myth. Salt really does make a great weed killer (herbicide), as it will kill just about anything that grows, but is so toxic it simply can’t be recommended in most garden settings.
Salting any type of planting will kill plants for months, years, even decades: a sort of scorched earth policy for plants of all sorts, leaving the ground absolutely barren for ages. The Romans are said to have salted the earth at Carthage in 146 BC* in order to destroy any chance of that civilization rebuilding. It’s that efficient at killing plants!
Even the much-hated herbicide RoundUp (glyphosate) pales in comparison to salt when it comes to environmental damage. At least glyphosate does decompose salt never does.
How Salt Works
When soil is salted, water will move from the lesser concentration of salt inside the root tissues to the greater concentration in the soil outside, causing cells to wilt then die. Source: laidbackgardener.blog
Salt kills plants by osmosis. Where there is more salt outside of the plant than inside, it will draw the water out of nearby plant cells, causing leaves (if applied by spraying) or roots (if watered in) to dry out and die. If you spray salty water on most plants, the leaves and possibly stems will soon turn brown, but they’ll probably soon put out new growth, as salt is a contact herbicide: it doesn’t travel through the plants’ vascular system and therefore only kills the tissues it touches. If it is watered into the soil, though, and kills the roots, that will kill the whole plant.
Salt also kills most soil organisms, both good and bad, including bacteria, fungus, insects, earthworms and slugs.
The Poison Is in the Dose
Of course, we humans use table salt all the time and we’re fine with it. So are plants… when the salt is highly diluted. In fact, both plants and animals (including humans) need both sodium and chlorine (table salt is sodium chloride: NaCl) for healthy growth … but only in small amounts.
Take a look at how many plants grow on the edges of bodies of water with high salt concentrations, like the Dead Sea or Great Salt Lake. There aren’t any, are there? Neither body of water has any fish either: they’re too salty.
Here, de-icing salt has killed the grass near the road. Treating any surface with salt will have the same effect. Source: turfgator.com
How much salt is too much? I hesitate to recommend ever using salt as a herbicide, so in fact the dose matters little. Even if you apply salt to kill weeds on a patio, sidewalk or parking lot where no growth at all for several years would be a benefit, remember that the salt applied will eventually be diluted by rainfall and soak into the water table or run off into nearby bodies of water. If everyone started doing this, it could eventually render the water locally unusable. Already, the use of road salt is causing salt levels in ground water and nearly bodies of water to skyrocket near many cities, a disaster for the environment gardeners blithely salting weeds would just make things worse.
Where You Never Want Plants to Grow
Salt certainly will kill weeds growing in walkways, but are you willing to pay the environmental price? Source: www.inchcalculator.com
I simply don’t recommend using salt as a herbicide, especially in or near gardens, lawns, other plantings or where there are tree roots. If you insist on using salt to keep weeds down in pavement or in cracks in a driveway or sidewalk, places where you never want to see plants grow, make sure to at least keep well away from anything growing. If, under your conditions, you’re sure that the salt will not reach the water table, you can spread a thin layer of rock salt (de-icing salt) in between bricks, pavers or stones to keep weeds away for years. Or dilute table salt or rock salt in water (about 3 parts salt per 1 part water), mixing until it dissolves, then (carefully) pour it on. But you’re playing with fire!
Be forewarned that salt is also highly destructive to concrete and paving stones, so by solving one problem, you might be causing another.
You’ve accidentally spilled salt on plantings? Soils can take years to recover if left on their own, but if you water regularly, this will gradually dilute the salt causing it to flow elsewhere.
I don’t recommend using salt to kill plants. Salt may be cheap, efficient at killing plants and even organic (hey, it’s a natural product!), but I feel the potential damage to the environment is just too great!
Learn to tolerate a few weeds rather than kill them. Then everyone will be better off!