Types of pre-emergent weed control products
Herbicides can be classified several ways, and based on your needs and preferences, there are a couple
different options of pre-emergent weed control for you to choose from. Ask your Lawn Pro which type of
pre-emergent product they are using.
Systemic or contact
Systemic herbicides enter the plant through the roots and leaves and move throughout the inside of the
Contact herbicides kill lawn weeds from the outside in. They attack the exposed parts of the plant,
killing the weed by reducing its ability to feed itself through photosynthesis.
Contact herbicides kill only the plant parts contacted by the chemical, where-as systemic herbicides are
absorbed by the roots or foliage and translocated (moved) throughout the plant.
Selective or non-selective
A selective weed control means you are selecting the type of weed you want to prevent. The chemicals are
formulated to kill certain types of weeds, and leave other wanted plant life alone. An example of a
selective herbicide is a pre-emergent weed control designed specifically for the removal of broadleaf
plants (leaves that have a flat, relatively broad surface). A pre-emergent broadleaf weed control will
remove the broadleaf plants without killing the established lawn in which the weeds grow.
A non-selective herbicide will kill everything it is applied to, even grass! You shouldn’t apply
pre-emergent weed control to newly planted grass. The chemicals in some weed controls can damage certain
types of grass. If you pick a variety that kills grassy weeds; whether it’s newly planted grass, or
seeds from a re-seeding, the pre-emergent weed control will likely kill any new desirable grass seed as
For example, if you have Bermuda grass, you won’t want to apply a non-selective herbicide directly to
your grass. You’ll instead want to find a selective herbicide that is the best pre-emergent weed control
for Bermuda grass.
Common brands of pre-emergent weed control
- Wow Supreme
- Andersons pro turf barricade granular
Organic pre-emergent weed control
It’s hard to imagine that killing a pesky weed can be done organically. However, there are some natural
weed control solutions that have worked for those that prefer a more environmentally-friendly solution.
Corn gluten meal is a powdery byproduct that comes as a result of the process for
milling corn. Corn gluten has become a common organic and natural pre-emergent weed control alternative
to synthetic chemical herbicides. It can be effective to control crabgrass and other lawn weeds.
Corn gluten works when the application of corn gluten is timed correctly, germinating crabgrass seeds
will form shoots (the part of the plant that turns into stems and leaves) but not roots, and will
Other organic methods for weed control are not considered pre-emergent, but may be a better choice for
special uses such as vegetable gardens. These methods include:
- hand-pulling weeds
- spot spraying weeds with an organic pre and post emergent weed control such as a 10% vinegar
- letting the plants die out in hot or cold seasons
- using shredded mulch in flower beds as a weed blocke