“A weed is a plant that has mastered every survival skill, except for learning how to grow in rows”. – Doug Larson
If your garden is like mine, you spend a lot of time weeding, preventing weeds, and complaining about weeds. In fact as I write this, my wife has just spent several days cleaning and weeding our perennial garden, and I spent a day edging and spreading mulch! Weed questions make up a pretty good chunk of the inquiries we get around the Garden Center as well. So this month I will try and answer the most common weed related questions gardeners ask us.
There are many ways to battle weeds in the garden. One of the most effective is prevention. This can be done in several ways, with a combination of one or more being the most effective.
• Pre-emergent herbicide. Products like Preen® which contains the chemical trifluralin (Treflan®) are the most commonly used pre-emergent products. When applied correctly, they prevent weeds from developing healthy roots and shoots. The first application should occur before weeds germinate in the spring, and reapply every 6 weeks or so, according to label instructions. These products need to be watered in to be effective, but heavy rains can reduce their effectiveness. For those that prefer an organic alternative, products containing corn gluten are also available, however the pre-emergent weed control quality of corn gluten is very highly debatable.
• Mulch. Any time the soil is turned, weed seeds are brought to the surface, where the sunlight spurs germination. A good layer of organic mulch applied after any sort of ground disturbance or cultivation is a great way to prevent weeds from emerging. I like to use shredded hardwood bark in my ornamental beds, and straw or compost in my vegetable garden. Just make sure the straw is weed free, and any compost has been produced with enough heat to kill weeds.
• Lots of cover. Mature ornamental plantings of perennials, annuals, or ground cover are fairly easy to keep weed free as long as the weeds have been prevented or removed before the plants canopy over. Any that do appear are usually easy to spot and remove.
Not much to describe here. I spent thousands of hours as a child doing this in our 1.5 acre vegetable garden! Very effective on annual weeds, but can be difficult on deep-rooted perennial weeds like dandelions.
Hoeing, tilling, and other cultivation methods can be very effective on small weeds. Just remember, any time the soil is disturbed weed seeds are brought to the surface. We call this Job Security!
Post emergent sprays.
Products like Roundup® (non-selective herbicides – meaning they will kill any plant they are applied to) are highly effective tools in your weed control arsenal. Used properly they can eliminate hours of backbreaking labor. I use non-selectives to maintain edges around the garden, kill weeds between plants (VERY carefully), and eliminate unwanted grass.
Selective herbicides can be used to eliminate broadleaf weeds in grassy areas, or to eliminate grass in ornamental plantings. The grass killers have to be used very carefully, and have a very complicated label – read carefully! You should have a separate sprayer for all classes of herbicides and insecticides/fungicides. I have 3 – one for Roundup®, one for broadleaf weeds in the lawn, and one for insecticides/fungicides. This prevents any cross-contamination from occurring. Always remember to read and follow the label carefully when using any chemical sprays.
Hope you have a great, weed free summer!