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Unwanted Garden Guests

Each spring, enthusiastic gardeners begin their year with delight at the prospect of growing selected vegetables and maintaining a beautiful landscape. Planting day is accomplished with energy and hope. Young plants start to grow with great potential to yield bountiful produce. And then the weeds start to grow.

Smiles fade, enthusiasm wanes, and the drudgery of weed control begins – not to mention the potential effects of other unwanted insect or disease pests. So, while the joy of gardening is a real thing, and the title of a book or two, weed control has taken the proverbial wind out of many a gardener’s sails.

You may be thinking that I’ll recommend a magical herbicide that can be sprayed anytime and will kill all the weeds and leave all garden plants alone. No, sorry.

Dr. Rosie Lerner, former Purdue consumer horticulture specialist, co-authored an Extension publication with Steve Weller, Emeritus Professor of Horticulture and Landscape Architecture, entitled “Weed Control for the Garden and Landscape.”

Although the publication is somewhat dated, it contains strategies that remain timeless. They wrote that the best strategies for controlling weeds include mulching, hand-pulling, using tools such as the hoe and rototiller, and preventing existing weeds from going to seed.

“Mulching around plants will go a long way toward reducing the ability of weeds to cause problems,” they said. “Organic mulches tend to cool the soil, as well as conserve soil moisture and reduce weed germination.” They suggested using such organic materials as chipped or shredded bark, straw, hay, grass clippings, and pine needles. Plastic mulch for warm-season vegetables and landscape fabric in landscape plantings can also be used.

“Don’t underestimate the power of your bare hands (well, make that gloved hands)!” they said. “Young weeds are very easy to pull, especially during or just after a rain.”

There are many different weeding tools to choose from, and each gardener has their favorite. I have even seen some homemade inventions that work pretty well. Larger gardens may require a rototiller or other weeding machine. They recommended shallow cultivation for weed control to avoid bringing deeply buried weed seeds to the surface, allowing germination and growth of a new crop of weeds.

Part of your attack plan is to prevent weeds from going to seed. Weeds have tremendous seed production capacity. “For example, a single dandelion plant can produce 15,000 seeds in one year, and each seed is capable of surviving for up to six years in the soil,” they said. “So, it is in your best interest to stay ahead of the weeds!”

In some cases, herbicides may be part of the solution, but keep in mind that certain herbicides may only work with certain garden plants. For example, selective herbicides for sweet corn may not work with green beans. Selective herbicides for the lawn may kill broadleaf weeds in turfgrass, but not work well in the vegetable garden. (“Selective” basically means that they kill certain weeds and leave certain crop plants alone). There are pre-emergent and post-emergent herbicides, and limits as to how big weeds can be for post-emergent herbicides to work effectively. There are non-selective herbicides, like glyphosate, that affect any plant they touch.

If using herbicides, carefully read and follow all label instructions, and make sure they are labeled for use on or around the plants you are spraying (especially if they are food plants). I have heard more than once of homeowners who have just grabbed a “weed killer” on the garage shelf and sprayed willy-nilly, only to end up with a disaster.

I think it’s also worth mentioning that some weeds provide pollen and nectar for native bees and other insects. Are there areas in the landscape where you could consider leaving some weeds like goldenrod, asters, or others (but not noxious weeds)? Could you tolerate a few weeds in your lawn? It’s something to consider.

For more information, search for the above-mentioned publication at Purdue Extension’s Education Store, https://edustore.purdue.edu.

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