Ask the Experts

When to Cut Back Perennials and Ornamental Grasses in Dallas Texas

February 6, 2023

Perennials and ornamental grasses are an important part of most garden landscapes. They add texture, color, and interest to your garden, even during the winter months. However, to keep your garden looking its best, it’s important to understand when the best times to cut back perennials and ornamental grasses are in Dallas, Texas. 

Understanding When to Prune and Why

Proper pruning technique and timing are critical to the health and beauty of your landscape. Pruning stimulates the release of growth hormones in plants, leading to an increase in foliage and flowers. If plants are pruned back too soon, then there is a good chance that new growth will occur before winter is over. In this case, a hard freeze will kill the tender new growth that is stimulated by pruning too early, and it will cause damage or death to the plant.

There is a risk involved with pruning too late as well. If you wait too long to prune perennials and ornamental grasses, they will not have adequate time to mature throughout the growing season. This makes them less likely to produce flowers or reach their full beauty.

In general, it’s best to cut back perennials and ornamental grasses in late winter or early spring, just before new growth begins. This will protect them against damage and give the plants enough time to regrow and bloom again in the summer. In Dallas, Texas, perennials and ornamental grasses can be cut back typically around February to March. This timing is a general guideline, though, and it is important to assess the following factors prior to determining when within this time frame is ideal for your plants.

Assess Your Plants Prior to Pruning

One of the main indicators that it’s time to cut back ornamental grasses is when the plants have gone dormant for the winter. This means that the leaves have turned brown and are no longer green. It is important to check the stem of the plant all the way to the base of the ground to ensure there is no green remaining. If necessary, scratch the stem of the plant to ensure the interior bark does not show any signs of green. This indicates full dormancy.

Another indicator to consider is seasonal weather patterns. It is beneficial to wait until the risk of any major hard freezes has passed. In Dallas, Texas, some winters are milder than others. In the event of a severe winter with multiple and prolonged ice, snow, and freezing events, it is best to wait until the end of winter is in sight to ensure your plant is fully dormant and no new growth occurs that may be affected by freezing weather.

What to Consider When Pruning

Some perennials and ornamental grasses may need to be cut back more severely than others. For example, ornamental grasses such as Mexican Feather Grass, Miscanthus, Gulf Muhly, and Switchgrass should be cut back to about 4-6 inches above the ground. On the other hand, perennials such as Coneflowers and Black-Eyed Susans may only need their dead stems trimmed back to their base. 

Some gardeners prefer to keep the dried stalks of perennials and ornamental grasses intact over the winter as they provide interest and texture to the garden, as seen in the photo below. If you prefer this look, wait until early spring to cut back your plants. 

Knowing when to cut back perennials and ornamental grasses is an important part of garden maintenance. By following these guidelines and considering the time of year, physical indicators, and seasonal weather patterns, you can keep your garden looking its best all year round.