CERTIFIED TEXAS EXPERT GARDENER — Management and weed control necessary for SETX lawn care

Published 12:02 am Wednesday, October 18, 2023

Gardeners, it’s time to take control of our lawns and provide much needed care.

Summers’ triple digit heat with sparse rainfall has wreaked havoc on lawns, turning once lush “green” carpeting into brown, straw-like “burlap” matting. As cooler temperatures have arrived, let’s review lawn management techniques to control weeds.

Weed groups are classified into categories: annuals, biennials and perennials. Effective management begins with understanding characteristics of the groups, as each is controlled and treated differently. Lawn management and weed control requires an increased level of detail, meaning there is a lot of information which will be divided into a three-part series beginning with weed basics.

Annual weeds begin as seeds, completing their life cycle in less than a year. Often, they are the easiest to control but produce an abundance of seed at the end of their life cycle, which means they often persist year after year. Annual weeds are further divided into two subcategories: summer and winter.

Summer annual weeds germinate in the spring, grow during summer, then flower and set seed in the fall. Seeds remain dormant throughout winter until the following spring, when they germinate to begin another growth cycle.

Summer annual weeds include cocklebur, morning glory, lambs’ quarters, common ragweed, crabgrass, pigweed, foxtail, and goose grass. There are many, many other summer weeds, but these are some of the most common in our area of SETX.

Winter annual weeds germinate in late summer, fall or winter, then mature forming seeds in the spring and early summer before dying. Seeds remain dormant during summers’ heat since high temperatures inhibit germination. Winter annual weeds include wild mustard, henbit, and sow thistle. There are numerous others.

Biennial weeds’ lifecycle is greater than one year but less than two. Fortunately for gardeners, there are only a few weeds in this group: wild carrot, bull thistle, common mullein and burdock.

Perennial weeds’ lifecycle is two years or greater and they are categorized by method of reproduction, known as simple or creeping. Let it be known that weeds falling into this category are the most difficult to control and require considerable effort to manage.

Simple perennial weeds often spread by seed, but if cut into pieces, can produce new plants. For example, if a dandelion or dock is cut in half, each plant part will produce new plants, thus creating two new plants. Other examples are buckhorn, plantain, broadleaf plantain, and pokeweed.

Creeping perennial weeds reproduce by roots which creep along the top of the soil or just below the soil surface with rhizomes, in addition to producing seeds. Examples: red sorrel, perennial sow thistle, field bindweed, wild strawberry, mouse ear, chickweed, ground ivy, nutsedge (nutgrass), torpedo grass, smilax, Virginia button weed and quack grass.

These are some of the most difficult weeds to control, as many of these weeds have roots and rhizomes, which grow deeply into the soil, some to a depth of one foot or more.

Attempting to pull the weed by grabbing the leaves, roots or rhizomes from the soil will allow the unwanted plant to regrow, or worse, double…which only exacerbates the problem!

Now you might be asking yourself, what can you do?

What is the best way to defend against weed invasions?

Well, one of the best defenses for controlling weeds is having a well-established turfgrass lawn. Most homeowners in southeast Texas have St. Augustine, Bermuda, Centipede or a combination of the three grasses.

Maintaining turfgrass requires a considerable amount of time and energy, mowing the lawn is the most time-consuming activity. It is important to note that before mowing the lawn, the mowers’ blades must be sharp, and the cutting deck height correctly adjusted to the proper height.

Never remove more than one-third of turfgrass growth when cutting the lawn. Remember grass blade height directly correlates to a deeper root structure, which is necessary for lawns to survive our blistering, triple-digit heat summers.

I suggest fertilizing with a slow-release fertilizer that will build a healthy and robust “green” lawn. Special note for lawns with Centipede grass: best not to use weed and feed fertilizers! It’s better to use a light dose of straight fertilizer mix such as 8-8-8 or 10-10-10.

This gardener prefers an organic approach, by adding a ½ to 1-inch layer of well-composted manure. Always allow grass clippings to remain on the lawn and form a thin layer of thatch, unless they are smothering the turf, then remove clippings.

Watering is also a key practice, allowing for optimal root growth and development. During times of sparse rain fall, supplemental watering is necessary.

Water deeply, since deep watering is more efficient than short, shallow watering, and forces roots to grow downward searching for moisture. Water when the wind is calm, saturating the soil, then stop watering to allow water to be absorbed into the soil.

Continue utilizing the water and soak method until the lawn receives about ¾ to 1-inch of water, which is the weekly requirement for most lawns.

Next week the discussion centers on herbicides and the weeds they control.

So long for now fellow gardeners, let’s go out and enjoy Shangri La Botanical Gardens Annual Scare Crow Festival. Visit shangrilagardens.org for more information. Hope to see you there!

Send comments and questions to Texas Certified Master Gardener John Green at jongreene57gmail.com.