Propagating Ornamental Grasses

Grasses are propagated mainly by division and seed. Some species can be grown from cuttings or from plantlets that form on certain grasses. Division is the only way to reliably propagate grasses and to perpetuate a plant's unique characteristics. Propagate named cultivars of ornamental grass by division only, to ensure uniformity. Many grass cultivars do not come true from seed, so a particular seedling mayor may not be identical to its parent. But most seed-grown grasses are reasonably like the type.

Seed

While volumes of information have been published on growing cereal grasses from seed, little data exists on growing ornamental grasses from seed. Germination rates, times, percentages, and the feasibility of planting ornamental grasses from seed are all open to experimentation. Many grasses are not available from seed, and some that are prove considerably expensive.

Some grasses can be directly seeded into the garden, but others must be grown from seed in the greenhouse. Often the seed is extremely fine, capable of blowing away in the slightest breeze. Other grasses can be directly seeded if drilled or placed beneath the soil.

In general, those grasses that can be grown from seed germinate in 10 to 20 days. Sometimes foliage emerges in 3 to 5 days; other times it may take 100 days or more to germinate. Some grasses prefer stratification of some kind prior to planting. Presoaking in warm water or chilling in damp sand are two seed treatments that have been practiced with ornamental grasses. Experiment with a small amount of seed rather than an entire crop. If little is known about direct seeding, it is better to start seedlings indoors and transplant them once they are established.

Despite apparent drawbacks, growing grasses from seed can often be rewarding and exciting. Many of the fine varieties and cultivars of ornamental grasses currently available were seedling variations themselves. If all grasses were grown from division, we would lose out on yet undiscovered individuals. Some grasses are extremely variable from seed, but others are reasonably like their parents. Often, it is not important for all the plants to be exactly identical. Many botanists and ecologists feel that seed- grown plants create a stronger plant community in the garden than do large populations of a single cultivar. They feel that plants grown from seed are hardier and can fight off insects, diseases, and environmental changes better than divided or asexually propagated plants.

Division

Different grasses are divided at different times of the year. Grass culms may separate easily by hand or may require a knife, a saw; or clippers to pry apart. Grasses with rhizomes, or under-ground stems, can be propagated by sprouting new plants from pieces of rhizome. Grasses with stolons, or above-ground runners, can be multiplied by rooting pieces of stolons. Always keep newly divided grasses from drying out. Protect them from hot sun and drying winds.

Cuttings

Some grasses will grow from cuttings of stems or other plant parts. Grasses that form thick culms or canes will often root from cuttings. Sugarcane (Saccharum officinarum) roots easily from cuttings of the cane. Successful cuttings have also been made from lemon grass (Cymbopogon citratus), fountain grass (Pennisetum spp.), and maiden grass (Miscanthus spp.). Because division is so easy, little work has been done with cuttings to date. However, research in this area is increasing, and new successes are being reported all the time. Grasses are being rooted with and without hormone applications.

Plantlets

Some grasses and sedges, such as umbrella sedges (Cyperus spp.), will form new plants from buds held in the terminal bracts. Simply cut the terminal heads and float them upside down in water. Provide high heat and humidity for fast results. New plants will form in the axils of the bracts. Take newly rooted plants out of the water and place in soil.

A few grasses are viviparous, meaning that plants, rather than flowers, form on their flower stalks. Propagate these plantlets by detaching them and placing them in soil, where they will take root. A good example of a viviparous grass is 'Fairy's Joke' tufted hairgrass (Deschampsia caespitosa var. vivipara 'Fairy's Joke'), which produces loaded stalks of plantlets. It is not uncommon to see the occasional odd plantlet on most grasses.

Comments

Back To Top