Our fall here at the Nursery was beautiful, with warm temperatures and sunny days. Then the bottom dropped out, and we've had record lows recently that have put us profoundly into winter weather. That means we've got to keep an eye on our grasses and consider their overwintering needs.

Overwintering in Containers
Grasses are generally low maintenance plants, and overwintering procedures are relatively simple, too. When overwintering grasses, one of the most important considerations is water level. During winter, warm

The poly houses did their job well during our first snow of the winter, keeping the grasses dry and protected.

season grasses go fully or partially dormant and cool season plants slow their growth, both of which greatly reduce water needs. If overwatered, grasses are susceptible to rotting and root damage, so they generallyprefer dry soils in winter. Take care to monitor soil water levels and keep containerized grasses on the dry side.

Temperature is, of course, intertwined with water needs. The majority of grasses, including the popular Calamagrostis, Chasmanthium, Miscanthus, Muhlenbergia, and Schizachyrium overwinter best in a cold frame with a clear poly covering. This not only protects the uninsulated roots in above ground containers, it also prevents precipitation from overwatering the plants. Panicum species and cultivars can do well outside of a cold frame with some monitoring. If you choose to overwinter outside, it is critical to track water levels because there is no protection from natural precipitation. If the containers are sufficiently moist, you may need to cover outdoor containers during rainfall to prevent overwatering and rot.

Panicum virgatum 'Northwind' in a coldframe transitions into dormancy.

In the Landscape
Perennial grasses in the landscape generally don't require any special treatment if they're hardy in your zone. However, newly planted grasses can be vulnerable to prolonged periods of severe cold and wet conditions.

Planting warm season grasses too late in the fall can be dicey and lead to plant loss. It depends on your climate, but here in Central North Carolina, we don't recommend planting warm season grasses past the end of October. Muhlenbergia capillaris and Pennisetum alopecuroides 'Hameln' are two popular grasses that can suffer if planted too late in the season. Cold, wet conditions can really challenge these heat lovers. On the other hand, we've planted Panicum species and cultivars (Switchgrasses) in December with no ill effects. It's important to know your grass and understand when they're actively growing, so you can plan your planting accordingly.

As with all of our growing recommendations, this advice needs to be adjusted to your specific climate conditions. For our customers growing out liners, we offer Grass Guides for most of our grasses. Give us a call or send an email if you're interested in seeing them.

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