The blue fescue appeals with its blue-green color and is wonderful for the steppe and rock garden. This is how to properly plant and maintain the grass.
Profile of blue fescue:
Scientific name: Festuca glauca
Plant family: grass family (Poaceae); formerly: (Gramineae)
Sowing time: Spring
Planting time: Spring (to Autumn)
Flowering period: June to July
Soil quality: gritty to sandy, calcipholous to lime-tolerant, nutrient poor
These information are for temperate climate!
Use in: flowerbeds, ground cover, green roofing, border, group planting, planters, roof garden, heather garden, rock garden, pot garden
Winter hardiness: hardy, USDA Plant Hardiness Zones: 4
Bee and insect friendly: No
Plant characteristics and classification of blue fescue
Plant order, origin and occurrence of blue fescue
The blue fescue (Festuca glauca) is an easy-care grass that was originally native to southern France. The genus Festuca includes a total of 300 to 400 deciduous and evergreen perennials. The term “blue fescue” stands not only for a single botanical species, but for a group of fescues that are visually very similar and in which a precise differentiation is only possible by counting the chromosomes. Most varieties, like the blue fescue, remain green for most of the winter.
Characteristics of blue fescue
The blue fescue is a crest-like, evergreen and perennial grass that forms hemispherical clusters about 15 to 30 centimeters (6 to 12 in) high and 25 centimeters (10 in) wide.
The silvery gray-blue and nine-ribbed leaves are smooth, flat, tightly rolled, linear and about 10 to 20 centimeters (4 to 8 in) long.
From June to July upright and dense, inversely egg-shaped, short-branched panicles appear, which are up to 10 centimeters (4 in) long and consist of spikelets with four to seven violet-colored, blue-green flowers. The blossoms of the blue fescue are characteristic, appearing first blue-green, later straw-colored.
After flowering, the blue fescue forms so-called caryopses, a type of nut that contains the seeds.
Blue fescue – cultivation and care
Dry, bright and sunny, although the blazing midday sun is allowed, but it thrives better in partial shade. Blue fescue can also be placed in relatively inaccessible places, dry corners without direct rain are just as suitable as slopes, which should not be in the hot sun, however. A distance of 20 to 30 cm (8 to 12 in) should be maintained if used as a bed border or lawn boundary. Small groups should be planted for green roofing. Due to the self-spreading, the plant cover quickly becomes dense and thus insulates the roof.
The blue fescue loves dry and permeable soil, does not need many nutrients and can also be cultivated on sandy or gravelly soil. Ornamental grass should not be planted in places that may be at risk of waterlogging. A drainage may have to be laid here, sand or gravel can be used for this. Basically, the sparse the soil, the more distinct are the blue tones of the plants. In recent years, the blue fescue has also been increasingly used for green roofing. The undemanding plant thrives excellently and requires no additional care.
No special precautions need to be taken when planting. However, the planting hole must not be too deep, the basis of the plant should still be above the ground. The blue fescue is usually planted in spring, but the plants are available all year round in containers so that they can be replanted at any time, except in frost. The plants cannot grow in extreme cold. It is worth adding some compost so that the grass can grow quickly at its new location. If you want to fill an area, you can easily use the blue fescue as a ground cover, here it applies that about 6 to 10 plants per square meter are needed. A distance of about 20 cm (8 in) should also be kept here so that the plants do not interfere with each other.
Watering should also only be considered during longer dry periods and then take place very sparingly. As long as the grass is not in the blazing hot sun, it will only need water in exceptional cases. This makes it one of the most undemanding plants ever.
Fertilization is absolutely unnecessary with the blue fescue and should not be done. The grass loves poor soil and grows better the less nutrients are available.
As a rule, the blue fescue does not need a prun, only the stems of the flowers should be removed after they have faded. If you want to prevent self-seeding, you should carefully watch the flowers and prune them early before the seeds have developed. In contrast to grass or lawn, mowing or cutting is not necessary with the blue fescue. So if you want to cover small areas with the attractive plant as ground cover, you will hardly have any work with it. Some gardeners recommend cutting the cluster back to the ground in spring. This primarily serves to make the growth more dense. However, if the ornamental grass grows densely anyway, this work is not necessary.
Festuca glauca is propagated either by seed propagation or dividing the perennial. Single-variety seeds are commercially available, which should only be covered thinly or better not with soil as it needs light to germ. The growing substrate should be kept moderately moist until the first seedlings appear. It is helpful to cover the pots with a foil, but this should be opened once a day to ensure air exchange and prevent possible growth of mold. Prick out seedlings as soon as they are about 3 – 5 cm (2 in) tall.
If you pick the seeds from your own garden, you have to expect that the grown plants look different from the mother plants, because of the cultivation they are not of the same cultivar. If you absolutely want to have the same variety, you should definitely multiply by division. Self-propagation can happen quite quickly with this grass, so if you want to limit it to a certain area, you should keep a close eye on it. Propagation by dividing the perennial is easy. In spring, the large cluster is cut, the cutting can be planted immediately at its desired location, while the mother plant remains on the site.
The blue fescue shows the most beautiful color when it is very hot and sunny. For a permanently beautiful look, it is worth cutting back the grass, but just a litte bit, which already looks somewhat torn into shreds after flowering. Since the cluster bare from the inside after a few years, it is important to divide the plants every few years. In winter, a blue fescue that is grown in a pot should be protected from too much rain. A prune or fertilization is not necessary.
Diseases and pests
In addition to all the positive properties of the blue fescue, there is another, it is practically insensitive to diseases, as well as pests of any kind do not find any particular taste in it. Snails also avoid it, making it the ideal companion anywhere in the garden.
Festuca glauca is hardy and does not require any special care to get over the cold season. Only the plants that are kept in tubs or bowls should possibly be protected with straw, garden fleece, leaves or bamboo mats, because here the severe frost can damage the roots. The blue fescue wrongly has the reputation of being short-lived and not surviving the winter. When choosing a location, care should be taken to ensure that neither waterlogging nor snow-break damages the plants. If the grass does not come safely over the winter, it can be assumed that it has been placed in the wrong location.
- never cut back in autumn, if at all
- if you want to be sure, you can cover the cluster with fir or leaves
Use in the garden
Classically, the blue fescue embellishes heather gardens. As a ground cover, it is well suited for small, sunny areas. It also comes into its own in mini rockeries in troughs or boxes, especially when it is combined with drought-tolerant plants such as common rock-rose (Helianthemum nummularium), cottage pink (Dianthus plumarius), stonecrop (Sedum) or houseleek (Sempervivum). It can also grow in the regular window box between summer flowers, but is rather short-lived here.
Attractive blue stalks carry the varieties ‘blue fin’, ‘blue fox’, ‘boulder blue’, ‘blue glow’ and ‘spring blue’. The variety ‘Elijah Blue’ is also popular and is often used for planting in the tub.