Overwintering Potted Ornamental Grass Indoors

(Question)

I have 4 pots of North Wind Ornamental Grass that is 4-5 feet tall. I want to move them in their pots into our heated garage over the winter and I would plan on watering them and leaving the lights on in the garage. There is no natural light in the garage. Will they survive?

(Answer)

You do not indicate how long your four panicum virgatum ‘Northwind’  switchgrass plants have been potted. Usually this ornamental grass is left in the ground, as it provides great winter interest.  The grasses grow in our zone in Toronto. Missouri Botanical Garden lists this plant and instructs it to be cut down to the crown in late winter. Leaving yours in pots would create overcrowding of the roots. These grasses need light, thriving best in full sun. Indoor lighting would not provide that. Tall plants as they are, they need light that surrounds the garage area, not just overhead lights. If you were to install LED grow lights, you would need to think of having some at a lower level than the ceiling. Incandescent lighting would not match natural light. Also, the temperature in the garage could dry out the plants, and since they would have little opportunity for light and growth, watering should not be done regularly.

After giving you many discouraging points of information, let me advise you to consider leaving the pots in place over winter, but adding insulation if harsh weather  is a threat. Wrap the pots in 2 inch styrofoam insulation, taping to hold the material in position. Wrap with some decorative burlap for aesthetics if you wish.

September 18, 2021