Whether in a pot or in a bed: ornamental grasses are a real eye-catcher in the garden. But to ensure that switchgrass, pampas grass, etc. please the eye for years to come, proper care plays a crucial role. This also includes rejuvenating pruning in spring. We explain when and how you should cut the ornamental grasses.
Cutting ornamental grasses: why do they need a rejuvenating cut?
Together with other foliage plants, perennials and subshrubs, ornamental grasses belong to the group of garden plants that delight with their delicate leaves, stalks and colors. Although they come from different parts of the world and belong to different plant families, all ornamental grasses have one thing in common: they provide structure and color to the garden. Most plants that fall into this (non-botanical) “category” do well with little care.
One of the most important care measures is:Pruning in spring. February and March are good for pruning because:
- Many ornamental grasses are wintergreen. Even if their stalks turn red or gold, they are still a real eye-catcher in the garden.
- Many ornamental grasses form seed pods in the fall, which then provide food for birds and insects during the cold season.
- In spring, the above-ground parts of most ornamental grasses dry. Dry blades of grass are highly flammable and should be cut off for this reason.
- The cold season leaves its mark: frost spots, rotten stalks, pests - only rejuvenating pruning can save the plants.
Cut hardy grasses in February
The ornamental grasses are divided into three groups. We summarize the most important features of these groups and explain what you should consider when cutting.
The first group is made up of hardy ornamental grasses that remain active even in the cold season. They grow mainly in spring and autumn, after the permanent frost has passed and before temperatures rise above 22 degrees Celsius. The right time to prune is in February before they sprout again.
Proceed as follows: Choose a frost-free day in February and tie the blades of grass together. Then shorten the grass by two thirds. Be careful not to cut back the grasses too drastically so that they can recover in spring.
Special case of angel hair: How to cut feather grass correctly
The feather grass slowly dries out in winter and its blades first turn gold and then brown. Only then is the angel hair cut back. In contrast to other winter-hardy grasses, feather grass is only shortened by half. Then the stalks are brushed off with a rake and dead plant parts are removed.
Cutting ornamental grasses: Deep pruning for pampas grass
Another special case is pampas grass. It is cut in February and March, shortly before it sprouts. The procedure is similar: the blades of grass are tied together and shortened to a height of 20 cm. Young plants are only cleaned out and only frozen areas and tips are removed.
Cutting summer green grasses: What should you pay attention to?
The deciduous grasses begin to sprout and grow again at the end of spring. They grow quickly and bloom in summer. In winter they turn brown, dry out and the above-ground parts of the plant die. It still makes sense to leave the stalks standing in winter as they offer frost protection. And some of the ornamental grasses look very attractive even when dry and therefore enrich the winter landscape.
The summer green grasses are cut back close to the ground in February and March.
Cutting ornamental grasses: Pennisetum grass does not require any pruning
Another special case is the Pennisetum grass. The wild plant can cope without pruning and the cultivated plants don't actually need any pruning. The Pennisetum grass is still cut in spring - on the one hand because it looks better when the new green blades appear. On the other hand, because dried stalks of pennisetum grass are highly flammable.
Cut switchgrass “Northwind” correctly
Switchgrass is actually a hardy plant. However, it cannot tolerate pruning during frost. In winter, the dried stalks protect the plant from rot. The “Northwind” variety is cut about 10 cm above the ground on a sunny or cloudy day.
Special case of miscanthus: Cut the grass blade by blade
Miscanthus is cut close to the ground like the other summer green grasses. However, since the stalks are very hard, you have to cut them off individually. It is best to use sharp pruning shears for this.
Don't cut Japanese grass, but divide it
Unlike othersOrnamental grass is Japanese grassa shallow rooter. The above-ground parts of the plant die in autumn, but provide frost protection for the roots in winter. Therefore you should only cut it in spring. The plant actually doesn't need any pruning and you can leave it out. Spring is the right time to divide the Japanese grass.
Should you cut or not cut evergreen ornamental grasses?
Evergreen ornamental grasses do not need pruning. However, you can check the plants in spring for frost damage, diseases and pests. If necessary, you can also thin them out a little.
Remove dead blooms from blue fescue in summer
Blue fescue does not need pruning in spring. But you can cut off the dead flowers in summer. In this way you prevent seeds from forming - and thus also their uncontrolled spread in the garden.
