So where did all the weeds come from?
The answer is, they were always there.
Weed seeds can remain dormant in soil for years, until the proper environment is created for them to thrive. Preparation of the soil is the common culprit for weed infestation. Tilling under the soil, while creating a nice seed bed, also brings dormant, buried weed seeds to the surface. Adding top soil to the area will bring its own weed seeds as well. Even processed loam will not be weed free.
Controlling Weeds with a Thick, Healthy Lawn
Weeds growing in a lawn disrupt the visual uniformity by their leaf width or shape, growth habit, or color differences between weeds and desirable turf-grass species. It is important to note, however, that weeds are symptomatic of a weakened turf, not the cause of it. Understanding this fact helps to explain the major reason for weed encroachment into a turf area. Thin turf, bare spots and poor growth are the reasons that allow weeds to invade desirable turf areas. These problems stem from several considerations that have never been recognized or dealt with properly. Among these are:
1. Improper turf-grass species selection.
2. Improper lawn soil management such as pH adjustment and soil compaction.
3. Improper turf management practices such as an inadequate fertilizer program designed to encourage healthy turf-grass growth by using both organic and synthetic sources of nitrogen.
4. Finally, physical damage caused by improper mowing height or even excessive wear patterns caused by foot or equipment activity, which probably could be altered.
Therefore, it becomes apparent that a healthy growing lawn turf is your first and best line of defense against weed encroachment.
Types of weeds:
Lawn weeds can be divided into two basic groups, broad leaf weeds and grassy weeds.
Weeds that complete their life-cycle in one growing season (annuals) or two or more years, (perennials), are both commonly found in lawns.
Now that we’ve learned weed seeds are unavoidable, how can we treat them?
Timing of herbicide (pre-emergent) application
Selective herbicides are classified as pre-emergence or post-emergence, depending on the time the control product is applied in respect to turf-grass and/or weed germination.
Pre-emergence herbicides: Pre-emergence herbicides are applied to the turf-grass site prior to weed seed germination and form a barrier at, or right below, the soil surface. These products prevent cell division during seed germination as the emerging seedling comes into contact with the herbicide.
Green-Up Lawn Food with Crabgrass Preventer:
This product can be applied in the spring for both pre and post emergent crabgrass control, up until the plant’s three leaf stage. This product provides season-long crabgrass control, plus it controls 30+ other grassy and broadleaf weeds. This product can be applied as early as mid March, and as late as the beginning of June, and still provide effective control. However, it is important to keep in mind that weather changes each year, and spring breaks at different times depending upon your location.
Crabgrass and Weed Preventer:
Use this product when you do not want to fertilize. It provides the same control as Jonathan Green Crabgrass Preventer plus Green-Up Fertilizer, (see above). You may want to make an organic fertilizer application with Organic Lawn Fertilizer just prior to applying Jonathan Green Crabgrass and Weed Preventer. Do not seed for 3 months after applying these products.
- Crabgrass does not grow in shade. In order to reduce your use of control product apply only to sunny area of the lawn.
- An application of Jonathan Green Love Your Soil at the time you apply either of these control products will make them more effective in controlling weeds and promotes healthy lawn growth.
- If Annual Bluegrass, Poa annua, has been a problem in the lawn, either of these products applied around Labor Day will provide control of this lawn weed. Annual Bluegrass is a winter annual. It germinates in the fall, survives the winter months and becomes aggressive in the early spring into the beginning of the summer months.
Organic Weed Preventer plus Fertilizer:
Organic pre-emergent control of many grassy and broadleaf weeds including crabgrass and dandelions.
Must be applied early in the spring as a pre-emergent, before crabgrass or broadleaf weeds germinate.
Contains Corn Gluten, feeds the lawn for 8 weeks.
Safe to apply where children and pets play.
Typically substantial control of weeds is achieved after successive applications over several seasons. By applying this product spring and fall over a two to three year period you can eliminate about 90% of all weeds.
Post-emergent lawn weed control
Post-emergent broadleaf herbicides are applied directly to actively growing weeds in the lawn. They are effective in controlling a great variety of weeds such as dandelions, plantains, chickweeds, ground ivy and many more. The key to successful broadleaf lawn weed control is that the granular control product must adhere to the surface of the weed leaf in order to be absorbed and provide control. Therefore the weed leaf should be damp prior to application for maximum control. Apply the control product to early morning dew or a lightly sprinkled lawn. Do not apply broadleaf weed controls when the temperature is above 85°F. Do not mow for two days prior or after application. Do not water or expect rain for two days after application.
Green-Up Weed & Feed Lawn Food:
This product controls over 250 broad leaf weeds including dandelion, chickweed, plantain and clover.
3 way action controls more weeds.
Provides slow-release fertilizer to promote healthy grass growth.
Lawn Weed Control:
If you have already fertilized, apply to control over 200 broadleaf weeds including dandelion, plantain, clover and chickweed.
This product does not contain fertilizer.
Directions: Apply to damp turf only where broadleaf weeds are present. This limited action will give very good control. DO NOT SEED FOR 4 WEEKS AFTER APPLYING THESE PRODUCTS.
Finally, since light is required for optimum germination of weed seeds such as crabgrass and goose-grass, cultural practices that favor turf-grass will increase turf density which will prevent light from reaching the soil surface. Please read a copy of my New American Lawn Plan which explains how to achieve a dense attractive lawn.