How to Grow and Care for Blue-Eyed Grass

Despite its name and appearance, blue-eyed grass is not a true grass. It is a wildflower with a clump-forming growth habit, narrow blade-shaped leaves, and clusters of blue-violet 1/2-inch flowers with yellow eyes.

This eastern U.S. native perennial is often found in large colonies in moist meadow areas and along river banks. The plant does not need special conditions, but it grows best in full or partial sun with moist soil on the acidic side.

Blue-Eyed Grass Care

Here are the main care requirements for growing blue-eyed grass:

• Grow in a sunny spot with moist, well-drained soil, even if the soil is relatively poor.
• Keep this perennial well-watered, and protect it from drought.
• Cut blue-eyed grass back after it is done flowering, if you want to keep it from self-seeding and spreading.
• Divide blue-eyed grass every two or three years to revitalize it, propagate new plants, and control its spread.

Rhizomes

Small groups of plants will readily spread by rhizomes and self-seed to form ground-cover colonies.

Light

Although it is tolerant of light shade, blue-eyed grass will flower better and show denser foliage growth when grown in full sun.

Soil

Blue-eyed grass does best in poor to average soil, but it must be moist and well-draining. It prefers an acidic or neutral soil pH of 5.0 to 7.0. Very rich soil is not ideal for these plants and causes a lanky habit.

Water

Blue-eyed grass performs best in moist soils. In native locations, it is often found in damp meadows and along streams, and it will soon decline if the soil is allowed to dry out for too long. It is best to water in the early morning hours.

During dry, hot periods, you may need to water daily, especially if the plants are growing in less-than-ideal conditions. This perennial normally needs about 1 inch of water per week, but this can vary considerably depending on soil composition, temperatures, and other factors.

Though applying mulch is normally a good way to preserve soil moisture, it is not in the case of blue-eyed grass. Mulch covering the root crowns encourages rot, so make sure to keep mulch away from the plant leaves and stems.

Temperature and Humidity

Blue-eyed grass grows well in temperate or chilly temperatures but can suffer when temperatures drop below 20ºF. It tolerates average or low humidity.

Fertilizer

An occasional application of compost will be sufficient to improve soil, but even that is often unnecessary. Chemical fertilizers should not be used, as the plant prefers poor soil conditions.

Types of Blue-Eyed Grass

In addition to the species plant, there is one notable cultivar of Sisyrinchium angustifolium, 'Lucerne'. This cultivar has notably larger flowers, up to 1 inch across, and it blooms considerably longer, sometimes well into late summer.

In addition, other native species of the Sisyrinchium genus are popular landscape plants, including:

• S. striatum (pale yellow-eyed grass): This is a South American native with yellow flowers that blossom in late spring and early summer. It is hardy in zones 7 to 8.
• S. bellum:This type is another form of blue-eyed grass, native to California and Oregon, and hardy in zones 7 to 8. It is very similar to S. angustifolium but is a better choice for dryer western gardens.
• S. mucronatum (needle-tip blue-eyed grass): This is another North American native, but it has a broader hardiness range, zones 3 to 8. It is a slightly smaller plant than S. angustifolium, with delicate star-shaped flowers.
• S. campestre (prairie blue-eyed grass): This type is very similar to S. angustifolium, but it is a smaller (6-inch) plant that is hardy as far north as zone 2 and blooms almost a month earlier in the spring.

Pruning

Colonies of blue-eyed grass can be shorn back after blooming is complete to prevent unwanted self-seeding. Some gardeners like to deadhead the spent flowers to promote new buds and a longer bloom period, but it is not essential. Use clean, sharp pruning shears.

Propagating Blue-Eyed Grass

Individual plants are relatively short-lived (living for only a few years), but once colonized, the spreading roots and self-seeding habit will keep a patch of blue-eyed grass flowers growing almost indefinitely.

Don't be surprised if the clump "travels" and moves around the garden as it spreads out from the original location, while the original plants die out. You can also perpetuate the colony by lifting and dividing the roots every couple of years. Here's how:

1. Use a shovel or trowel to dig up an entire intact clump of blue-eyed grass in the spring, as new growth is just beginning.
2. Shake loose most of the soil, or spray with a hose to remove the soil.
3. Gently tug apart the root clump into sections. Each section should have at least three or four growth shoots.
4. Replant the sections in the desired locations, and water well until new growth is well established.

Blue-eyed grass responds best to division two or three years to rejuvenate the clump, but if your goal is simply propagation, you can also dig up small offset plants around the mother plant and transplant them. Self-seeded volunteer plants can also be transplanted in this way.

How to Grow Blue-Eyed Grass From Seed

Blue-eyed grass is usually planted from potted nursery starts in the spring, or it can be grown by seeds directly sown in the garden during the fall or started indoors in late winter. You'll need to plant several specimens, so they can cross-pollinate and produce seeds.

It is a relatively fast-growing plant, though it may take two seasons to flower if you plant it from seeds. If you collect seeds from plants, remember that they need cold, moist stratification to germinate. Plants started from seeds may not flower until their second season, so be patient.

1. Scatter the seeds over the area where you want them to grow in the fall, and let the winter cold provide the necessary stratification.
2. If you prefer to start them indoors in late winter, then store the seeds in the refrigerator for six weeks.
3. Plant the seeds in small pots, just barely covered with moist potting mix (they need light to germinate).
4. Keep the planted seeds in a bright location between 50℉ and 60℉ until they germinate and sprout.

Overwintering

These hardy wildflowers need no particular winter protection, but you may want to cut down the plants to remove seed heads, which can cause undesirable self-seeding. Leave the seed heads in place to attract birds.

How to Get Blue-Eyed Grass to Bloom

Bloom Months

This plant will bloom from May through June. However, with regular watering, blue-eyed grass may bloom further into the summer.

What Do Blue-Eyed Grass Flowers Look and Smell Like?

Blue-eyed grass is not an extremely showy plant, so it is favored mainly by native plant enthusiasts. The flowers are only about 1/2 inch across, and they tend to open in the morning and pucker up later in the day as conditions warm.

Encouraging More Blooms

Blue-eyed grass is normally quite generous with its flowers, provided it is getting plenty of sun and moisture. Keep in mind that blue-eyed grass prefers relatively lean soil, and it may paradoxically resist blooming if growing in soil that is too rich.

If your plants fail to bloom, try withholding fertilizer. Even excessive mulch can make the soil too rich, so neglect is often the best strategy for robust blooming. Blooming may slow down if plants become overly crowded, so be sure to divide the clumps every few years.

Deadheading Blue-Eyed Grass

Deadheading spent flowers may also prompt the plant into a longer bloom period, since it nudges the plant into producing additional flower buds.

Common Problems With Blue-Eyed Grass

When growing in favorable conditions, there are very few pest or disease complaints with blue-eyed grass. But keep an eye out for the following:

Collapsed Plants

If the plants are collapsing at the soil line, they are succumbing to root rot, which most often happens if the soil is covered with a dense layer of mulch or plant debris. If you mulch at all, make sure to keep an open area about 3 inches around the base of the plants.

Leggy Plants

Planting in rich soil or over-fertilizing can result in lanky plants. It's not necessary to feed this plant.

From: thespruce