Turf and Landscape - Spring Is Here

In the last week, plants in the landscape have advanced significantly. The following are some observations.

1. Cool season turf grasses have finally greened up across mid-state and southern Delaware. along with greenup, we also have growth activity in perennial weeds in lawns, turf areas, and landscapes. While early spring is not the ideal time to control perennial weeds such as wild garlic or plantains, herbicide applications may be warranted in some cases. For example, dandelions are in bloom and you want to knock them back with broadleaf herbicides before they go to seed. Garlic and Star-of-Bethlehem should be controlled now and you may wish to reduce down some of the winter annuals with a postemergence herbicide. Unfortunately, many of the winter annuals such as bittercress have already gone to seed. However, many are just now flowering and you can reduce seed loads for weeds such as chickweed and henbit by applying broad leaf herbicides now (but don't wait). Crabgrass preemergence programs should be applied very soon in turf.
2. Many ornamental plants are flowering now and some are starting to leaf out. Evergreen plants will be starting to break in the near future. Those plants that have specific foliar disease problems (such as crabapple scab in crabapples or needle casts in evergreens) will need to have fungicide applications to protect this new growth as it emerges.
3. Dropped and dead flower petals can create conditions for botrytis if wet conditions exist. Consider fungicide applications in susceptible plants.
4. Fruit trees will need protectant fungicides throughout the flowering period. Plan for applications every 10-14 days from now to fruit maturity.
5. Many spring bulbs are flowering now or will be flowering in the near future. If these beds are to be kept as perennials, you need to maintain the foliage of these bulb plants after flowering. Do not mow or cut back.
6. Insect activity will build as the temperatures warm up. Be aware of the insects that are prevalent in your landscapes and time control measures when they are near full emergence.

Gordon Johnson, Extension Agent, Commercial Horticulture, UD, Kent County