Gardeners who have taken advantage of our mild winter days this year are well aware that these moderate temperatures are giving the weeds a head start. Two are more than obvious in my yard, henbit and creeping spurge.
Most years henbit (Lamium amplexicaule) is tolerated in my lawn; the seed germinates in fall and grows through the winter. This year it is growing faster with the warm days and, where the square stems touch the ground, it roots to form a new plant.
Naturalized from Europe, henbit is a difficult weed to control. Preferring moist, cultivated soil, henbit can be identified by the small purple flowers that bloom atop a stack of green leaves with toothed, yet rounded edges.
The best chemical control for henbit is to apply a pre-emergence herbicide such as Halts or Preen in late summer or fall.
Pre-emergent controls prevent certain weed seed from sprouting; with henbit’s life cycle beginning in fall those with bad infestations may need to mark their calendars for a September application. (Take note, autumn applications of these products may negatively affect the germination of fall seeded fescue.)
Post-emergent controls kill weeds after they have started growing, the greatest success achieved when young weeds are treated.
Three-way herbicide products are effective against henbit and selective — they won’t kill stands of neighboring grass, but the first precaution with an Internet search reads “corrosive, irreversible eye damage (for humans and animals); do not get on skin or clothing.”
That’s too toxic for me, so I will spend a little time each day pulling the weeds, root and all and removing the pieces from the garden or lawn.
As with any war, knowing your enemy is the key to victory and healthy troops (or in this case a healthy lawn) is the first line of defense.
One popular organic pre-emergent is corn gluten meal.
This product suppresses weed germination and at the same time feeds and encourages a thick healthy lawn.
Other organic post-emergence contain clove or citrus oil and may damage grasses as well as weeds.
Always read labels carefully before applying and follow all instructions.
Another very different weed is making an early stand in parts of my lawn — creeping spurge.
Preferring hot weather to proliferate and dry compacted or gravely soils; where this perennial weed got a foothold last summer, it has never died completely back this winter.
Interestingly this is the first weed I have seen referred to as completely worthless as nothing will eat it. Control will be similar to henbit, but pre-emergence products will be applied in late spring.
LeeAnn Barton, Stillwater, can be emailed at email@example.com.