Quick-establishing grass cover crop with an extensive fibrous root system. Annual ryegrass is especially good at holding soil, capturing leftover nutrients, improving soil structure, and producing a dense stand that competes with weeds. It tolerates wet winter conditions well and can produce substantial spring growth.
When to sow: Sow from late summer through early fall for winter cover. It can also be spring-sown.
How to terminate: Mow or cut in spring before seed heads mature. Annual ryegrass can regrow after an early mowing, so a second cutting may be necessary. Do not allow it to set seed unless you want it to return.
From Territorial Seed Company. 99% germination rate.
Lolium multiflorum, Annual Rye Grass seeds
How to Use Your Cover Crop & Native Seed Packets
Each seed packet is measured to cover 1 sq ft, 5 sq ft, 25 sq ft or 100 sq ft, depending on the size you chose.
Sowing Instructions
When to sow: Fall is ideal in Portland. The soil is still warm for germination, and fall rains keep seedlings watered. Some seeds (like meadowfoam or clovers) can also be spring-sown.
How to sow:
Rake the soil lightly to create good seed-to-soil contact.
Scatter the contents of the packet evenly over the area (don’t worry about perfect spacing).
Gently press or rake seeds in so they make contact with the soil. Do not bury deeply — most native and cover crop seeds need light to germinate.
Water: Fall rains usually do the job, but water lightly if the weather turns dry.
What to Expect
Traditional Cover Crops (rye, peas, fava, daikon, crimson clover, buckwheat, mustard): Grow quickly, protect soil, and build fertility. In spring, chop them down or mow before they set seed. Some (like rye) can also be crimped into a mulch.
Living Mulches (red fescue, dwarf yarrow, creeping thyme, low clovers): These stay low and provide long-term weed suppression and ground cover. Shear lightly as needed, but they don’t require replanting every year.
Pollinator Wildflowers (Clarkia, poppy, gilia, flax, meadowfoam, coneflower, blanketflower): Not classic cover crops, but they add beauty and attract bees, butterflies, and beneficial insects. Many reseed naturally.
Spring & Summer Management
Chop-and-drop: Cut plants at the base and leave them as mulch (peas, fava, clovers).
Mow: Use on ryegrass or cereals to turn them into quick mulch.
Crimp: Flatten tall rye or grains at flowering to create a long-lasting weed barrier.
Shear perennials: Yarrow, thyme, and sedges can be trimmed back after bloom.
Self-seeders: Flowers like poppy, clarkia, and meadowfoam will often reseed themselves. Leave some seed heads if you want them back next year.
Quick Tips
Cover crops = soil builders.
Living mulches = weed suppressors.
Wildflowers = pollinator magnets.
Tulle or row cover can protect young seedlings from birds and slugs until established.