Cold-Tolerant Annuals 
An annual is any plant that would naturally survive only one season, going from germination to death in less than a year. Annuals are grown for their continuous blooms during their short lives.
Cold-tolerant annuals, also referred to as hardy annuals, can add early color and interest to the landscape. In the early spring when there’s still a good chance for frost, Minnesota is limited to cold-tolerant annuals. Cold-tolerant annuals have the ability to withstand cooler temperatures in the spring and will frequently withstand temperatures slightly below freezing in the fall.
Cool weather annuals are also cold tolerant; however, they thrive only when the weather is cool. Once the summer gets warm, their blooming slows. Examples of cold-tolerant/cool weather annuals are Calendula, Godetia, Lobelia, Pansies and Violas.
Tips for Growing Healthy Cold-Tolerant Annuals
| Acclimate tender plants |
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Start by keeping the plants outdoors during the day any time the temperature is 40 degrees or above. After several days, they should be able to handle the cooler temperatures. |
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Be prepared to move them indoors when the temperature dips below 40 degrees. |
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The plant should be able to withstand a light frost after several days of acclimation. |
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| Frost tolerance |
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This varies by the specific variety of annual. |
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Pansies and Violas can tolerate several degrees below freezing, so they are usually the first annual planted. |
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Most hardy annuals tolerate light frosts, but not freezing. |
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Average last frost date in Minneapolis is May 10. |
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| Light |
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Varies with each variety, refer to plant tag. |
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| Locations |
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Perfect for containers or great by themselves, annuals combine well with other early spring blooms. Tuck a few into a summer mixed planter for early color while the summer plants fill out. |
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Annuals also thrive when planted in: |
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Beds and borders |
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Gardens interspersed with spring flowering bulbs |
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Window boxes |
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| Soil |
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Containers: Use any peat-like mix such as Bachman’s Mighty Earth™ Potting Soil. For best results, replace soil annually. |
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Ground Beds: Amend soil with compost or peat moss once the frost is out of the ground. |
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| Transplanting |
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Annuals have a very fine, fibrous root system, so ease them out of their pots gently. The outside of the root ball may be a mat of white roots. |
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Make several shallow cuts through these roots to encourage outward growth. |
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Plant them at the same depth they were growing. Annuals don't do well when planted deeper. |
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| Spacing |
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Varies with each variety, refer to plant tag. |
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| Water |
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After transplanting, water immediately. |
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Frequently water. |
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| Fertilizer |
| Containers: |
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Add a slow-release granular fertilizer at time of planting. |
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Feed with water-soluble fertilizer weekly. |
| Ground Beds: |
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Add granular fertilizer at time of planting. |
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Feed with water-soluble fertilizer monthly. |
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| Protection |
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Annuals planted in containers and ground beds should be covered with frost cloth if frost is forecasted. |
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Remove frost cloth once the sun rises and temperature is above 32 degrees. |
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| Protection |
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Snip out any leaves that develop milky white patches, usually caused from plants that are not fully acclimated. |
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Cold-Tolerant Annuals
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Cool-Tolerant Vegetables
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| Calendula |
| Dianthus |
| Forget Me Not |
| Godetia |
| Pansy |
| Snapdragon |
| Stock |
| Sweet Alyssum |
| Sweet Peas |
| Viola |
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| Broccoli |
| Brussels Sprouts |
| Cabbage |
| Cauliflower |
| Kale |
| Kohlrabi |
| Lettuce |
| Peas |
| Radish |
| Spinach |
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Related Bachman's Information
Recommended Products
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Bachman's-grown annuals and vegetables |
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Quality seeds and seed starting supplies |
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Plant fertilizer |
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Potting soil, compost and peat moss |
Bachman's Floral, Gift & Garden Centers
Your local garden expert since 1885.
bachmans.com | ©Bachman's 2012
Select source information provided by the University of Minnesota Extension, www.extension.umn.edu.
Last Updated: March 2012
