Yard Full of Dead Weeds in Spring -- Plant Seed or Use Weed Killer?

Pre-emptive Strike

• If the weed seeds have not yet begun to sprout, you may want to apply a pre-emergent weed killer. Pre-emergents restrict the root growth of new seedlings. Because the root cannot develop, the weed dies while it is very small, often before it can produce leaves. A pre-emergent can eliminate most of the weed seedlings in the yard. Some pre-emergents last for only a few weeks, others up to three months. On the downside, pre-emergents are not selective. They also prevent desirable seeds from growing, but plants with established root systems are left unharmed. So when using a pre-emergent, add loveliness to your yard by planting nursery plants, sod or plants you have started indoors that have established roots.

Controlling the New Crop

• Once the dead weeds have been cleared away, you may see new weeds that had previously gone unnoticed. This new crop of weeds can be controlled with a post-emergent weed killer. Post-emergent herbicides, absorbed by the weed, disrupt internal systems at they travel through the plants much like water or nutrients do. Post-emergents are effective in the spring before weeds become well established but while they are actively growing. Different types of weeds respond differently to weed-killing chemicals. Knowing what weeds are in the yard and purchasing weed killer labeled for those weeds will increase the chances of success.

Smother and Condition

• Nonchemical solutions to weed problems should be considered. Applying a heavy mulch layer to the yard will suffocate weed seeds and growing weeds. Planting seed would not be an option, but transplanting nursery plants could keep the yard attractive. One advantage to mulch is that it removes weeds while adding organic material to the yard. Seed planted the next spring would have better soil without the competition from weeds.

Heat and Wait

• For very bad weeds, covering the yard with black or clear plastic can also be effective at killing weeds. The plastic prevents water from reaching the plants. Black plastic also prevents weeds from getting sunlight. The plastic can also increase the temperature of the soil, killing seeds with heat, especially in the hottest months of the summer. The disadvantage is that the yard cannot be planted until the plastic has had a chance to work and has been removed.