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does boiling water kill weed seeds

The war between weeds and gardeners has raged for hundreds of years. Each battle involves a strategic assault on the ever-invasive weed. The eradication process ranges from homemade recipes to professional applications, and still the weeds exist. Some concoctions work better than others, and the weed dies. The victory, however, may be a Pyrrhic one when the adjacent plants suffer from the chemical strike. A mixture of salt and water to kill weeds in grass and flowers is one such method that kills the weeds but may damage the surrounding foliage and soil.

Water is the mainstay of plant growth and reproduction. The temperature of the water determines whether the plant lives or dies. Warm or cold water do little damage to most plants and benefit weeds. Boiling water not only kills the plant but also the seeds that may lay dormant in the soil. The boiling water produces almost instantaneous results. The heat destroys the plant and root tissue, causing instant shock. The plant withers and dies within a day or two. Boiling water works well for walkways and garden paths or driveways. But you must use care in the lawn or garden to avoid the hot water splashing on the remaining plants or grass.

The Problem With Salt

Salt restricts the moisture intake of the root system and dehydrates the leaves of the plant. Both of these problems may injure or kill the plant. Nutrients dissolve into the water and travel through the roots to the rest of the plant. A mixture of salt and water in the soil can limit root formation and growth. The lack of water causes leaves to dry out and stops photosynthesis. Food production stops for the plant. The plant starves to death. This process is why salt kills the weeds in the landscape. But the salt is not selective and affects the roots of all the plants in the area.

The best way to use a salt and water mix to kill weeds in the lawn or flower bed is the direct approach. A 2-to-1 ratio of water to salt kills plants when applied directly to plant tissues. A funnel directs the saltwater to the offensive weed and keeps the mixture off other plants in the area. The water does permeate the soil, and roots do not always grow directly under the plant. The damage to the plant begins once the ground is saturated with the saltwater. Avoid injury to surrounding plants by watering the favorable plants so the salt leaches into the ground below the root zone.

The use of a pre-emergent herbicide keeps weed seeds from sprouting and interrupting the landscape and flower garden. Cutting or digging out the weed is another approach to weed removal. If you must use a saltwater solution for weed control, consider replacing tender plants in the area with plants that are more salt-tolerant, such as boxwoods, junipers and chrysanthemums. Corn gluten is a natural pre-emergent for the landscape that adds nutrients to the soil. A layer of mulch in the flower bed keeps the weeds at bay around the flowers. Continued use of saltwater contaminates the soil and eventually the soured soil will not grow anything.

Dealing with problems can be that way in life. You can choose to dwell on the problem or see it as a path to build something preferable. BTW, since the cardboard will suppress weeds below it, the new weeds sprouting in your garden will be easier to pull!

Last summer I found that boiling water will kill weeds, and kills them quick. However boiling water takes time and a large individual crabgrass would take a whole pot of boiling water to kill the weed. My question asks if anyone knows of any other home remedies for weeds. Spot treatment for crabgrass is all I need. Small yard.

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If you want to boil water for nearly free you can get a solar cooker that does this. And then get free hot water that you can use to keep killing those unwanted plants forever.

Instead of trying to kill the weeds as is, you could think of them as future fertilizer. Get some cardboard or newspaper, lay it on top, and start “lasagna gardening” by putting compost on top of that. You’ll be able to plant in it come spring. One thing I’ve learned from weeds is that you can try to go down to their level, but you end up opening up the soil for weed seeds that are embedded in the ground.

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