Monthly Theme: PART II: Weeds, weeds, and more weeds!

Just when you thought you knew enough about weeds, here we go again with more information about some of the most troublesome offenders in our yards. Last month we reviewed Dandelion (Taraxacum officinale), Ground Ivy (Glechoma hederacea L,), and Canada Thistle (Cirsium arvense). In this issue, we will dig into (pun intended) three more common weeds.

The first weed I’d like to discuss is Crabgrass (Digitaria spp.) (see cover photo). Crabgrass is also called finger grass. It is a low-growing annual, which spreads by seed or from root nodes in the soil. Its wide blades have pointed tips with a rosette in the center. It loves a hot summer and can actually grow to 2’ tall. It dies in the winter and returns in the spring.

In my yard, I deal with Crabgrass more in my lawn than the flowerbeds, but let’s be honest, it grows wherever it wants to. It actually doesn’t kill the grass, but it doesn’t look good as it spreads in large patches across the lawns. I find it incredibility difficult to weed. You really need some muscle to pull up these stubborn weeds even when the soil is moist.

As we discussed last month about Ground Ivy, Crabgrass can be controlled by creating a healthy lawn; i.e., fertilize, soil aeration, regular mowing, and overseeding to create a thick lawn. For those who use chemicals, apply a pre-emergent herbicide in early spring. These herbicides prevent weed seeds from growing to maturity by stopping the root system from developing. However, seeds can remain viable for up to 3-years in the soil. Be careful not to get these chemicals in your flower or vegetable beds.

An alternative to herbicides is corn gluten meal, which is a natural fertilizer that can inhibit crabgrass growth and seed germination.

About 2-years ago a new weed starting growing in my yard called, Shepherd’s purse (Capsella bursa-pastoris). If you don’t have issues with this one yet, count your blessings. It grows fast and furious. Fortunately, it’s easy to weed the shallow young branched taproot, which includes fibrous secondary roots. Just watch out for its scalloped rosette of leaves and pull them out quickly. If you don’t weed it when it is still just leaves, a flowering (white to pale pink flowers) stem will grow up to 30″ tall. As always, remove the entire root and weed before the flowers go to seed.

If you prefer, you can manage Shepherd's purse with a number of pre-emergent and post-emergent herbicides. Although, five countries have found this weed is resistant to herbicides.

Shepherd’s purse gets its name from the way the seedpods look like the purses or bags that European shepherds used to carry. When the mature seedpods burst open, the seeds get distributed by Mother Nature.

Shepherd’s purse seedpods are edible, but the leaves and mature seeds can cause indigestion. They are not on my dinner menu, but the peppery pods are used in Chinese cuisine.

Chickweed *(Stellaria sp. & Cerastium spp.)*

I’ll end this issue with common Chickweed (Stellaria media). It’s part of the Pink Family (Caryophyllaceae). Chickweed is a winter annual weed that thrives in damp areas. Besides being a difficult weed to manage, it is a pool for plant viruses and insects. It can generate 800 seeds and take 8-years to eradicate. It grows in thick, low mats only 2” high. The oval shaped leaves are dark green and the little white flowers have 5-petals.

Like the other weeds we have discussed, the best way to control small patches of Chickweed is by digging it out before it flowers. I find it tough to weed. The fibrous roots grip the soil like Velcro. Again, organic mulch layers will help control weed growth.

If you elect to use herbicides, find a product with glyphosate, flumioxazin or a combination of those chemicals. In Ohio, it has become quite a worrisome weed in wheat and oat crops.

The entire Chickweed plant is edible, but only if you don’t use chemicals. It is said to taste like spinach and can be eaten cooked or raw. Maybe that’s our solution to the weed problem – we should start eating our weeds instead of digging them up and tossing them out!

GENERAL ADVICE FOR PREVENTING WEEDS

Remember that herbicides might feel like a quick fix, but those weeds will return yearly. For your lawn, a healthy soil and sod will afford less room for weeds to grow and thrive.

1. Weed early, weed often, and don’t let them go to seed!

2. Keep your garden tools clean as you work your way around the various garden beds.

3. Mulch, mulch, and more mulch. Check out my previous blog on mulching.

4. Buy clean mulch, compost, etc. so you don’t introduce new weed seeds to your landscape.

5. Don’t over or under fertilize.

6. Mow on a regular schedule.

7. If you are going to kill off an area of weeds using a cover of choice, do so 6-8 weeks before you plan on seeding or planting in that location.

8. Water at the base of your plants – no need watering the weeds!

9. Consider where you are planning your garden bed. Avoid areas close to weed fields or areas heavily weed-filled. Create a weed-free barrier between the weedy area and your garden bed.

I hope you have enjoyed learning about various weeds these past 2-months and good luck keeping these nasty intruders out of your yard.

“Once in a golden hour,

I cast to earth a seed,

And up there grew a flower,

That others called a weed,”

Alfred Tennyson

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