Turf - Start Planning Now for Late Summer Renovations

Plan now for weed control where turf is to be renovated in late summer or early fall. Information on renovation steps follows.

If a complete renovation of a turf area is to be done, one option is to apply 2 applications of glyphosate herbicide, three weeks apart. Allow sufficient time for any remaining weeds to die after the second application before renovating. Ideally, turf areas should be irrigated to encourage weed growth prior to applying glyphosate as it will not work well on drought stressed weeds. Glyphosate is not totally effective on some perennial weeds such as nimblewill. For troublesome perennial weed patches, Basamid soil fumigant may be an option. Basamid is applied as a granule and is watered in. It performs best if it is tilled in or is tarped with plastic. Research has shown good control of nimblewill, bermudagrass, and creeping bentgrass by fumigation with Basimid. It also controls many soil born pests (diseases and insects) and kills weed seeds and perennial propagules. One advantage to this approach is that seeding can be done 7-10 days after treatment. In contrast, 2 applications of glyphosate will require a minimum of 4 weeks lead time. Another consideration when doing fall renovations is reseeding restrictions for preemergence and postemengence turf herbicides. Read the label for each product that you use and make sure you will have enough time between the last application and desired reseeding date. Examples of reseeding restrictions: Dimension herbicide single application will require a 3 month waiting period before reseeding, 4 months with a split application; Barricade herbicide has a 4 to 7 month waiting period before overseeding depending on the rate used.

Gordon Johnson, Extension Horticulture Agent, UD, Kent County