Best Control Product:
Quinclorac 75 DF or any variant such as Drive 75 DF
Clover is very common and easily identified. Three , wide, leaves grow on each stem clumped together in mats of clover. Clumps of clover can range in size from one to two stalks all the way up to continuous clumps covering thousands of square feet. The stems of clover are covered in a fine hair. White to pink tinged flowers appear throughout clover patches in the summer. Clover grows on an above ground stem, called a stolon. The creeping above ground growth habit can and will suffocate turf grass over time.
Where and When:
Clover can be found year round in turf. In is perrenial and will keep occurring in the same spot each year, growing in size with out intervention. Clover becomes most noticable in early summer when the plant thrives and produces flowers. The flowers can remain from late May through September.
Look for clover in any lawn but it is particularly noticeable in poorly fed lawns because it will maintain a deep green color even when turf is not. The reason for the green color is clover produces its own nitrogen. Clover does not have one specific area in a lawn where it grows best but rather can grow in any portion of the lawn.
Clover Control Procedure:
Clover can be controlled with most broad leaf herbicides like 2,4-D or dicamba but it can take multiple sprays to control even a small patch. The best control product for clover may surprise you in that it is typically used for the post emergent control of crabgrass, it is Quinclorac ( the common trade name). Products that contain quinclorac are the generic product Quinclorac 75 DF (a dissolvable granule), Drive 75 DF (a dissolvable granule), Quincept ( a liquid concentrate), Q4 ( liquid concentrate), and many others.
Apply Quinclorac using a mid to fine droplet size and be sure to cover all of the leaf area of each individual plant. Use of a surfactant or dish soap will help the product stick to the plant. Dry weather is best. One treatment with quinclorac is all that is necessary when applied properly, within a few days the clover will curl and flip over, a sure sign that control has been achieved. If there is remaining clover, which can happen due to rain or poor coverage, repeat an application after 14 days.
Mixing the dry quinclorac with water can be tricky. It is difficult to dissolve it properly. The best method is using a separate mixing jug, like an empty one quart Gatorade bottle or similar. Mix the quinclorac with water in the jug and use a surfactant, a must when dissolving any granular product. Shake vigorously and pour the dissolved mixture into your spray equipment, preferably through a screen to ensure the product has been dissolved. Once it is in suspension it will stay dissolved for a period long enough to complete the treatment. One final, and most important note; whenever you use a dry dissolvable product you must use a diaphragm pumping mechanism. If a wet-able powder or granule is used with a piston pump backpack sprayer it will destroy it. Either purchase a diaphragm pump backpack, which you should be using anyway, or if a piston is all that is available use a liquid concentrate instead.
Organic Control Methods for Clover :
In many organic lawns clover is desirable because it naturally fixes nitrogen levels by producing a glut of the nutrient. Mowing high will blend clover in with the turf and it will only be noticeable while in flower. Clover also attracts honey bees which are a critical part of our Eco system, making clover even more desirable. There are seed blends available with clover included or just sole clover blends.