Spring Grass Seeding May Fill In Bare Areas
Normally, spring is not considered the ideal time to overseed a cool season bluegrass or fescue lawn because of the shorter establishment period before summer and the increased issues with weeds. However, if done properly and with attention to maintenance, spring might be a viable option.
Best time to attempt spring grass seeding
The best time to seed in the spring is mid-March through early April. Like fall seeding, the soil must first be prepared. The recommended method is verticutting. A verticut slices grooves in the soil that allows for the necessary seed and soil contact for germination. Simply scattering the seed on the ground usually results in a poor stand and a waste of time and money. Very small patches can be roughed up with a garden rake.
Once the soil is prepared the seed can be broadcast. Then the fun of overseeding begins as the soil surface must be kept moist through germination and into early establishment. This means light, frequent water applications applied as needed, based on weather patterns. The good news is that in the spring temperatures are cooler and more overcast, and rainy days are likely to reduce the watering demands typically found during hot September days.
Grass germination times for spring seeding
The length of time it will take for the grass seed to germinate will depend on the temperatures. Expect at least two to three weeks, or more, for emergence. Once the seed is up, reduce the frequency of watering to as needed. By that I mean, water when the seedling grass shows signs of stress, such as wilting or turning a bluish cast.
Care after spring grass seed germinates
Spring seeded turf has a very limited root system. My recommendation is not to even attempt spring seeding unless you are committed to watering during the summer. Without regular summer applications the spring grass is likely to die in the dog days of summer, which means you are right back where you started and out your time and money.
Spring seeded turf will also need a little more fertilizer to get it up and growing. At seeding apply a starter type fertilizer. Apply a second application about four weeks after germination using a high nitrogen source of fertilizer such as 30-0-0, and, if possible, find a formulation that contains a percentage of slow release nutrients. This helps spread out the feeding and reduces summer stress by not being under such a lush application of nitrogen.
Problems with spring grass seed germination
One of the historic problems with spring seeding has been excessive crabgrass germination. Thin turf areas and disturbing the soil results in a bumper crop of this pesky weed. Fortunately newer crabgrass control products can help us overcome this problem. The product Dithiopyr (active ingredient) is recommended for spring seeding as it can be applied later into the season and still provide good control.
This product actually works as a pre-emergent and on seedling crabgrass which has already germinated. In most seasons it can be applied in early to mid-May and still provide excellent season long control. In fact, some labels on the product indicate it can be applied as soon as two weeks after germination, or when the new grass is 2 inches tall.
January and February is the time to decide whether to seed this spring or just wait until fall and hope for a summer miracle. No matter what you decide, planning will lead to success as well as knowing the proper steps.