Traditionally, pre-emergent crabgrass control is applied in the spring. Even more traditionally, it is applied about the same time as the forsythia blooms, which is usually mid to late April in Central Indiana. However, with today’s technologies, tradition is no longer the norm. One can now apply dithiopyr (Dimension) well into late May or early June and get excellent pre and post-emergent crabgrass control. One can also apply pre-emergent in late fall to early winter and get excellent crabgrass control for the next season.
Products that work well for late fall to early winter applications are prodiamine (Armortech Kade 65 WDG) and dithiopyr (Dimension). Applying a fertilizer with either of these products is the ideal way to apply in this time frame.
Parameters for applying are:
- Soil temperatures at or below 50 degrees Fahrenheit, but above freezing.
- Spread rate minimum of 175 lbs per acre.
- Active ingredients per acre vary with geographic locale. Be sure to apply the correct active ingredient for your area.
The benefits of this application:
- Dormant fertilizer applications increase carbohydrate reserves in roots, rhizomes, and stolons. They also promote early spring green-up and turf density. These applications avoid excessive top growth that can occur with spring-applied fertilizers.
- Saves time in the spring when time is hard to find.
- Season-long pre-emergent control of crabgrass and some broadleaf weeds (see product label).
- Saves time and labor over spraying large areas, especially, if you consider having it custom applied.
Ask your Advanced Turf representative what products are available and the proper rate to apply in your geography. Thinking “outside of the box,” when it comes to controlling crabgrass, could be of real benefit to you!
