1. Preparation
Potted ornamental grasses can be planted at any time, as long as the ground is workable. Spring is the preferred season, but summer planting is also possible, provided you pay extra attention to watering during the initial period. In early spring, the plant may not look like much, but don’t be fooled—it will develop beautifully once established.
2. Location & Conditions
Location – Most ornamental grass varieties thrive in a bright, warm spot with well-drained soil. Partial shade can also work, but the grass may take longer to establish.
Soil – Ornamental grasses are not particularly picky about soil type and can grow in most soils. However, proper drainage is crucial to prevent excess water from accumulating. Poor drainage can lead to difficulties with overwintering and overall plant health. Ensuring good drainage is the most important factor for the survival and vigor of ornamental grasses.
Before planting, make sure the soil is free from perennial weeds, as they can intertwine with the grass roots and become difficult to remove. If the soil is too heavy, it can be improved with sand or compost.
3. Planting
Dig a hole twice the size of the root ball and plant the grass at the same level as the soil surface. Water thoroughly after planting and keep the soil moist until the grass has established itself.
4. Fertilization
Do not fertilize newly planted ornamental grasses during the first year, as their roots are often more sensitive at this stage. From the second year onward, fertilization is beneficial and can be replaced with soil improvement by mixing organic matter into the soil around the plants in spring.
A handful of manure and well-decomposed compost can work wonders for the plants each spring, especially if you have poor soil. Excessive nitrogen fertilization can lead to more leaves than flowering spikes and may also weaken the stems, making them more prone to bending under snow and wind. Large ornamental grasses may need an extra nutrient boost during the growing season. Nettle water, chicken manure, compost, or grass clippings are great organic options.
5. Maintenance
Since the stems are often hollow, they should not be cut down in autumn. Trapped water and moisture can lead to rot and frost damage, which may prevent the grass from surviving the winter.
Instead, cut ornamental grasses back in early spring. A good rule of thumb for most varieties is to trim about 5 cm above the ground. However, some species, such as fountain grass (Pennisetum), require a different pruning method. New shoots emerge higher up on the old stems, so cutting them too low will affect their appearance. Fountain grass should be trimmed about 20-25 cm above the ground.
Larger grasses can be tied together “around the waist” with string or a band before cutting. This makes trimming easier with sharp tools, as the stems can be quite tough!
6. Overwintering
For extra winter protection, especially in colder zones, cover the grass lightly with spruce branches or leaves. However, the most crucial factor for survival is good drainage.
If you have planted ornamental grasses in pots, move them under a roof or to a more sheltered location if possible.
Author: Johanna Damm
Fact-checked by: Erik Hoekstra
Last updated: 2025-03-15