How Long Does It Take Bermuda Grass to Germinate When Over-Seeding?

Timing and Germination

• The best seasons to over-seed Bermuda are spring and fall. Warm spring weather encourages seedling establishment before hot summer weather arrives, while fall means less weed seed competition for struggling grass seedlings. Average germination times vary between five and 14 days for Bermuda when over-seeded correctly. In general, seeds with their outer hulls removed sprout faster than those with their hulls intact -- seedlings must break through this protective layer. Choose unhulled seeds for rapid fall establishment or use a hulled and unhulled mixture for spring seeding projects.

Sowing Strategy

• If you have a cold snap in spring or fall, do not spread the seeds until air temperatures reach 75 degrees Fahrenheit -- this threshold corresponds to a 65 F soil temperature. Bermuda grass seeds need warm soil to stimulate germination. But the seeds cannot simply lay on the soil surface. The germination time also depends on seeding depth. Carefully rake the grass blades until the seeds settle approximately 1/4 inch deep in the soil. Seeds planted too deeply cannot reach sunlight and fail to germinate, while seeds planted too shallowly do not have the soil nutrients and moisture available to sprout correctly.

Competition

• Because you are establishing sprouts in a competitive grass environment, some Bermuda seeds will not germinate from reduced nutrient and moisture availability. To increase your germination success, mow your existing lawn to 1/2 or 1 inch high, based on the cultivar. Over-seed after mowing so the seeds get as much light as possible. The new sprouts have a chance to photosynthesize effectively with short grass blades surrounding them. Long grass blades block sunlight to the potential seedlings, causing germination failure in both spring and fall.

Moisture Availability

• The new seeds need consistent moisture to start germination and establish themselves in the soil. Water your over-seeded area daily for approximately 2 weeks. You should see seedlings filling in the lawn's bare areas. Do not allow the lawn to become waterlogged because this will kill seeds or wash them away. Once your seedlings are approximately 2 inches tall, water your lawn once a week to maintain your new and established grass.