Saturday, January 16, 2010

Weed Control without Chemicals

"Weed control without chemicals" may bring up unpleasant thoughts of getting down on your hands and knees in the yard on a hot day and pulling out stubborn weeds by hand or other means. But weed control without chemicals needn't be so primitive or back breaking work. Below I will discuss a variety of weed-control methods to be used in planting beds and should be used in conjunction with each other. Weed control without chemicals can be tough work, and I want you to work smarter, not harder. No need to revert to the Stone Age!

Weed Control Without Chemicals: The Foundation

The first smart idea in a project of weed control without chemicals is to prepare the plot of ground in question. Just as in a construction project, laying a good foundation is very important. By "foundation" I mean the state of the ground where your plants will be growing. Implement these ideas before you plant, so that you'll get off to a good start in your project of weed control without chemicals.

Killing Weeds Through Soil Solarization

Soil solarization is a preventive, organic method of killing weeds and their seeds…before they sprout! This method is usually used BEFORE planting your plants and shrubs.The advice below is meant for homeowners wishing to start out with a clean slate, or re-landscaping a weed-filled patch of land in such a way as to reduce to a minimum the hassle of weed control in the future.

For those in need of soil solarization, installing landscape fabrics can be difficult in existing landscapes but with a little patience and ingenuity, it is possible. As I said above that “weed control without chemicals wouldn't mean going back to the Stone Age”, and landscape fabrics are a case in point. Landscape fabrics are a hi-tech ally in the battle against weeds.

Using Garden Mulch

As the final element in a good "foundation" for your bed of annuals, perennials or shrubs, you should apply garden mulch on top of the landscape fabric. Many skip right to mulching in the project of weed control without chemicals, but I do advise you to lay the landscape fabric first: it will lengthen the life of your garden mulch.

Any decomposing mulch will work: Bark dust is an excellent choice. It not only provides mulch, but as it decomposes over the years, will provide additional organic material, and eventually natural fertilizer. In some cases, it provides a natural barrier to certain insects too.

If you can tolerate the odor as it decomposes, grass clippings from your mowed lawn are good. However, if spread thin enough the odor will be limited.

Fallen leaves from trees is another source. However, they will promote mildew or mold which will spread into your plants and even your house. So, maybe not a good choice unless fully decomposed.

Weed Control Without Chemicals: Pre-Emergent and Post-Emergent Organic Herbicides, Selective and Non-selective Herbicides

“Selective herbicides” refers to herbicides that attack only certain plants or grasses. Unfortunately, your resources for selective herbicides are extremely limited. You may have to revert to “man made” herbicides. If you do, ALWAYS READ AND FOLLOW LABEL DIRECTIONS!

“Non-selective herbicides” refers to those that attack or kill whatever they contact, so be very careful here. There are several options to choose from on the organic or non-man made herbicides.

"Pre-emergent herbicides" refers to applying herbicides that attack weedy plants at the source: their seeds. That is, they act to inhibit seed germination before the plants in question even have a chance to announce themselves to the world above! Corn gluten is a pre-emergent herbicide used for weed control without chemicals. Remember, corn gluten will inhibit the seed of "good" plants from germinating, too, so don't use it in planting beds where you're starting plants from seed.

“Post-emergent herbicides” refers to herbicides that attack and kill weedy plants after the seed has germinated and the weedy plant is above ground with leaves.

For weed control without chemicals, distilled vinegar is an excellent choice! If the weeds are relatively young or small, mix with water at a 50% rate and a few drops of liquid dish soap. The dish soap is a wetting agent making penetration faster and better. For older or larger weeds, use the vinegar at 75% or full strength with the same rate of dish soap. Even plain old household vinegar is effective if you have only young weeds to deal with in your planting bed. However, be careful here. It’s non-selective so don’t use it in your lawn (unless spot treating weeds) or any where else that you want to keep desirable plants. When using vinegar as an herbicide: apply it directly onto the weeds ONLY!

Again, VINEGAR IS NON-SELECTIVE and will harm plants that are inadvertently exposed to it. For this reason, vinegar isn't especially effective for battling lawn weeds: you'd almost inevitably end up with too much collateral damage to your grass. But vinegar is a fine organic alternative in planting beds, as long as you watch where you're spraying!

It's the acetic acid in vinegar that gives it its herbicidal abilities. The higher the percentage of acetic acid in the vinegar, the better. Vinegar used for cooking purposes is relatively low (5%) in acetic acid, so repeated applications will be necessary if you'll be applying it on full-grown weeds. Alternatively, you can try to buy the super-strength vinegar in stores that cater to the agricultural community.

In Case You Still End Up Pulling Weeds

With landscape fabric and garden mulch in place, the bad news is that, even then, you may still get weeds. But the good news is that those weeds will be very easy to pull out. Pulling weeds embedded in mulch is not nearly as difficult as pulling weeds embedded in soil. Thus with a good "foundation," you may not even feel the need to bother with the corn gluten and vinegar: 5 minutes of easy pulling here and there should get the job done.

One exception to this may arise: if the integrity of the landscape fabric has been compromised, weeds may strike down roots in the soil beneath, making them difficult to pull out. In this case, water the area in question beforehand. It's usually easier to extricate weeds from moist soil than from dry soil.

1 comment:

Unknown said...

Thanks for this article! These are some great ways to do weed control without using harsh chemicals. I think I'll have to try some of these.