Time of year: Deadnettle is a winter annual weed that primarily emerges in the fall. But the flowering and seed set beginning in early spring. Plants die with hot, dry weather in late-May and June.
While warm-season lawns are dormant in the winter, many weeds are just starting to become active. These weeds are known as winter weeds. They can be annual, biennial or perennial in regards to life cycles, and be very difficult to control. Annual winter weeds germinate in the fall and winter and grow actively in the spring. After they flower in spring, they die and disappear before the summer. But only to return in fall or winter when new seeds germinate.
Damage: Henbit will happily take advantage of the thin, moist areas in your lawn, especially those areas that are shaded. Each plant can produce up to 2,000 seeds that can take root and keep it coming around for years.
Damage: Like other mints, deadnettle is an aggressive grower that spreads like wildfire anywhere it can get a foothold. Getting rid of deadnettle weeds is much more challenging than dealing with many other annual weeds. This is because they tend to go to seed before mowing season even begins.
Mouse-ear chickweed, hairy bittercress, henbit, deadnettle and poa Annua are common annual winter weeds that may invade your dormant lawn this fall and winter. Learn more about each of these winter weeds below and take control of your lawn before they do.
Time of year: Poa Annua is a cool-season grass weed that starts germinating in late summer or fall as soil temperatures fall below 70 degrees Fahrenheit. It continues to germinate throughout winter, allowing several flushes of germination at any one site throughout the season.
Damage: Poa annua grass is typically a problem in the lawn because it dies back in hot weather, which can make unsightly brown spots in the lawn during the height of summer. It also thrives during cool weather, when most lawn grasses are dying back, which means that it invades the lawn at these susceptible times.
What it is: A broadleaf weed that normally acts as a perennial in the north; however, here, it has the ability to act as a winter annual weed due to our climate conditions
Winter weeds are probably the most annoying;, they are an annual bluegrass also known as poa annua . This annual weed has two periods of germination. The first period is in the late summer, usually in early September. The second is in late winter/early spring, usually late February to mid-March.
While the northern parts of the US are in the process of hunkering down for the winter, the milder temperatures of the southern states are providing the ideal temperatures to control many troublesome weeds in what soon will be dormant lawns.
Most of these weeds can be treated with broadleaf weed control products, which are available at hardware stores, garden centers and home improvement centers. Lawn care companies like Spring-Green also offer programs that are designed to keep these weeds from becoming a major nuisance in your lawn. In many cases, these weeds distract from the uniform appearance of the lawn and will often overtake the desired grasses.
The Different Types of Winter Weeds
Since annual bluegrass is in the grass family, broadleaf weed control products will not be effective. The product that is usually applied to control annual bluegrass is a pre-emergent weed control product.
Even though these lawns may be dormant, many weeds are just starting to become active in the fall. These weeds are known as winter weeds. They can be annual, biennial or perennial in regards to life cycles, and these winter weeds can be very difficult to control.
Pre-emergent weed control inhibits the formation of a new plant from the seed the plant leaves behind. Annual bluegrass is a prolific seed producer. The same pre-emergent weed control product that is applied to control crabgrass will also control annual bluegrass.
What Are Some Common Winter Weed Control Methods?
Winter annuals germinate in the fall, grow during the winter, and then develop flowers and set seeds in the spring and finally die when the weather turns hot during the summer. The seeds they leave behind will germinate in the following fall.
The ones that are most troublesome are the winter broadleaf annual weeds, which include common chickweed, henbit, lawn burweed, large hop clover knawel and parsley-piert.