Can rutabagas handle frost during their growth cycle?
Written by
Paul Reynolds
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Unlike other veggies, rutabaga has a special relationship with cold. Rutabagas will transform starches into sugars when subjected to light frost, producing a flavor experience that isn't found in any commercially available root. I've harvested rutabagas long after December snows, with their flavor-enhancing while other crops perished.
Beneficial Frost Range
- 28-32°F (-2-0°C): Enhances sugars without damage
- 20-27°F (-6--3°C): Requires mulch protection
- Below 20°F (-7°C): Risk of frozen roots
Protective Measures
- Apply 6-inch straw layer before hard frosts
- Use row covers with stakes to prevent contact
- Mound soil around root shoulders
Harvest Timing
- Dig roots when soil is workable
- Avoid harvesting frozen-solid ground
- Post-frost storage boosts sweetness
The use of mulching methods shows a difference between life and death. I will place straw above burlap for my climate zones 3-5, as this method creates air pockets that insulate better than loose materials. This has saved my crops from death due to a polar vortex that dipped to -15°F (-26°C).
Signs of frozen or frostbitten damage are translucent or transparent leaves and waterlogged roots (now mushy). Healthy rutabagas will survive some cold but will lose all firmness when frozen and thawed (removing mushy things is acceptable - just compost). If the roots were firm when thawed, the rutabaga was still healthy before the cold.
Strategic planting dates use the benefits of frost. Growers in the North should tailor their maturity to early frost periods. For example, my trials in Minnesota indicated rutabagas seeded in September developed 22% more sugar than ones seeded in August when both were harvested after three light frosts.
Read the full article: How to Grow Rutabagas: Expert Guide for Home Gardeners
