How To Grow Ornamental Grass From Seed

If you want to add movement and texture to your garden without a big expense, learning how to grow ornamental grass from seed is a fantastic skill. This simple step-by-step guide will walk you through the entire process, from picking the right seeds to planting your new grasses in the garden.

Ornamental grasses are surprisingly easy to start from seed. They offer a huge range of sizes, colors, and forms. With a little patience and the right technique, you can grow a beautiful display that comes back year after year.

This main process covers everything you need to know. We’ll break each part down into easy-to-follow steps. The key to success is understanding the needs of your specific grass seeds, as some have special requirements.

What You’ll Need to Get Started

Gathering your supplies first makes the job smoother. You don’t need fancy equipment. Most of these items are probably already in your gardening toolkit.

Seeds: Choose a variety suitable for your climate zone.
Seed Starting Trays or Pots: Clean pots with drainage holes are essential.
Seed-Starting Mix: A sterile, soilless mix prevents disease.
Spray Bottle or Gentle Watering Can: For keeping the soil moist without disturbing seeds.
Clear Plastic Domes or Plastic Wrap: To maintain humidity.
Grow Lights or a Very Sunny Windowsill: Most seeds need light to germinate.
Labels and a Marker: Trust me, you’ll forget what you planted where.

Step 1: Choosing Your Ornamental Grass Seeds

This is the most important step. Not all ornamental grasses are grown the same way. Check the seed packet for two key pieces of information: your USDA Hardiness Zone and whether the grass is considered an annual or a perennial in your area.

Some popular and relatively easy choices for beginners include:

Fountain Grass (Pennisetum)
Blue Fescue (Festuca glauca)
Japanese Forest Grass (Hakonechloa) – often needs a cold period.
Switchgrass (Panicum virgatum)

Also, note if the seeds require any special treatment, like cold stratification, which we’ll cover next.

Step 2: Understanding Seed Pre-Treatment (If Needed)

Many perennial ornamental grass seeds have built-in dormancy to survive winter. To trick them into sprouting, we sometimes mimic nature.

Cold Stratification: This means seeds need a period of cold and moisture. You can do this by mixing seeds with slightly damp sand, placing them in a sealed plastic bag, and putting them in the refrigerator for 4-8 weeks (check packet for exact time).
No Treatment Needed: Many annual grasses and some perennials are ready to sow directly from the packet. Always read the instructions.

Step 3: Sowing Your Seeds Indoors

Starting indoors gives you a head start and protects tiny seedlings. The best time to start is usually 6-10 weeks before your last expected spring frost.

Fill your clean trays or pots with moistened seed-starting mix. Gently firm it down.
Sow the seeds on the surface. Most ornamental grass seeds need light to germinate, so do not bury them deeply. A light dusting of mix or vermiculite is often enough.
Label each pot clearly with the grass type and the date.
Use your spray bottle to mist the surface thoroughly.
Cover the tray with a clear plastic dome or loose plastic wrap to retain humidity.
Place the tray in a warm location or on a heat mat. Most grasses germinate best at 65-75°F.

Light and Moisture After Sowing

As soon as you see the first green sprouts, remove the plastic cover. This is crucial to prevent mold. Immediately move the seedlings to a bright location under grow lights or on a sunny sill.

Keep the soil consistently moist but never soggy. Bottom watering is a great method here—place the tray in a shallow dish of water and let the soil soak it up from the bottom.

Step 4: Caring for Seedlings

Once your seedlings have their first set of true leaves (the ones that look like grass, not the initial seed leaves), they need a bit more care.

Thinning: If multiple seedlings sprout in one spot, snip off the weaker ones at soil level with scissors. Crowded seedlings won’t thrive.
Feeding: After a few weeks, you can begin feeding with a very diluted, balanced liquid fertilizer every other week.
Air Flow: A gentle fan on low nearby helps strengthen the stems and prevents fungal issues.

Step 5: The “Hardening Off” Process

You can’t move tender seedlings straight from indoors to the garden. They need to acclimate to outdoor conditions like sun, wind, and cooler temperatures. This 7-10 day process is called hardening off.

Start by placing your seedlings in a shaded, sheltered spot outside for just 1-2 hours.
Gradually increase their time outdoors each day.
Slowly introduce them to morning sunlight, avoiding the harsh afternoon sun at first.
By the end of the week, they should be staying out overnight if temperatures are mild.

Step 6: Planting in the Garden

After hardening off, your grasses are ready for their permanent home. Choose a site that matches the grass’s light requirements (full sun for most).

Prepare the planting area by loosening the soil and mixing in some compost.
Dig a hole slightly larger than the root ball of your seedling.
Gently remove the seedling from its pot, teasing the roots apart if they are pot-bound.
Place it in the hole at the same depth it was growing in the pot.
Backfill with soil, firm gently, and water deeply.
Space plants according to their mature width on the seed packet.

Ongoing Care and Maintenance

Your work is mostly done now! Ornamental grasses are famously low-maintenance.

Water regularly during the first growing season to establish a deep root system.
Most grasses don’t need much fertilizer; too much can cause them to flop over.
In late winter or early spring, before new growth starts, cut back the previous year’s dead foliage to about 4-6 inches from the ground.
Divide clump-forming grasses every few years in spring if the center begins to die out.

Troubleshooting Common Problems

Even with the best care, you might encounter a few hiccups. Here’s how to handle them.

Seeds Didn’t Germinate: They may have been old, sown too deep, or needed a pre-treatment you didn’t provide. Always check seed viability and instructions.
Seedlings Are Leggy and Falling Over: This means they are not getting enough light. Move them closer to a light source or use grow lights.
Mold on Soil Surface: Caused by too much moisture and poor air circulation. Remove any mold, let the surface dry a bit, and increase air flow.

FAQ Section

How long does it take for ornamental grass seeds to grow?
Germination can take anywhere from 10 days to a month, depending on the species and conditions. Growth to a garden-ready size typically takes a full growing season.

Can I just scatter ornamental grass seeds?
While some hardy native grasses can be direct-sown, starting them indoors gives you much better control over moisture and temperature, leading to a higher success rate. Scattering often results in uneven germination and competition from weeds.

What is the best time of year to plant ornamental grass seeds?
For most perennials, start seeds indoors in late winter to early spring. For annual grasses, you can start them indoors a few weeks before your last frost or sow them directly in the garden once the soil has warmed.

Do ornamental grasses grown from seed bloom the first year?
Some fast-growing annuals might, but many perennial grasses focus their energy on root development in the first year. You can expect them to reach their full flowering potential in their second or third growing season.

Is it cheaper to grow ornamental grass from seed?
Absolutely. A single packet of seeds can produce dozens of plants for the cost of one or two potted grasses from a nursery. It’s a very economical way to fill a large area or try multiple varieties.