11 Popular Annuals You Can Overwinter in Your Garage

Annuals are plants that go through their entire lifecycles in a year. True annuals die off every winter, but even some tender perennials behave like annuals in cold climates. 

Several common garden plants become dormant or semi-dormant during the winter. This means you can revive them in the spring as long as you store them properly when it gets cold. 

One of the best places to overwinter these plants is in your garage. Below are 11 popular annuals you can overwinter in your garage and revitalize in your garden the following spring. 

Amaryllis

	botanical name Hippeastrum spp.
	sun requirements Full sun to partial shade
	height 2-3 feet
	hardiness zones 7-10

Amaryllis bulbs are popular flowers that bloom indoors during the winter. This makes them perfect holiday gifts for loved ones with a green thumb and fun late-season flowers to add to your garden. When you plant them indoors, you’ll get luscious red, salmon, and red and white bicolor flowers that can last beyond the winter holidays.  

In cold climates, they grow as tender annuals, but you can overwinter the bulbs in your garage. Cut their flower stalks and leaves down to an inch from the bulb. The bulbs will go dormant so you don’t have to worry about watering them until the start of the next season. As long as you don’t water them and keep them in 50-60°F (10-16°C) they will remain dormant.

Garden Geranium

	botanical name Pelargonium x hortorum
	sun requirements Full sun to partial shade
	height 1 to 3 feet
	hardiness zones 10-11

Garden geraniums are the most popular garden plants in the Pelargonium genus of geraniums. These beautiful flowers form large clumps of bright white, pink, and red flowers that gardeners love to plant outside or in containers. These beautiful flowering plants grow as annuals in cold climates. 

To overwinter these annuals in your garage, simply stop watering them and let their soil dry up a few weeks before the first possible frost. Remove your plants from their containers or beds and gently remove the soil without damaging their roots. 

Gently clip off the flowers and leaves at the base nodules near the roots. If you see any dead growth, cut it off with pruners. Check for any insects, including aphids, and remove them before storing. Hang them upside down in your garage, ensuring the temperature is between 45 and 55°F (7-13°C). You can also store them in an open paper bag. You can soak the plant’s roots in water before you do this to ensure they’re ready to store.

Geranium ‘Gerwat’ ROZANNE

	botanical name Geranium ‘Gerwat’ ROZANNE
	sun requirements Full sun to partial shade
	height 1-2 feet
	hardiness zones 5-8

Rozannes are some of the most popular geranium cultivars you can overwinter in your garage. Just before the first freeze, dig them up and carefully put them into a large pot or container. Check for any insects that may be living on them and carefully remove them or treat them with organic neem oil. Once you transplant them, cut them back by about half their size. 

These beautiful flowers should last the winter as long as you follow a few steps. Moisten the soil once every week to give them enough water to overwinter. Check and make sure they still feel heavy and alive through the cold season.

Move them outside once the weather warms up in the spring and the chances of frost have passed. You may need to transplant them and give them a good fertilizer to stimulate their new growth. 

Tuberous Begonia

	botanical name Begonia x tuberhybrida
	sun requirements Partial shade
	height Up to 1 foot
	hardiness zones 9-11

Tuberous begonias are easy plants to overwinter in your garage. They grow them as annuals in cold climates and after their magnificent flowers bloom, their bulbs go dormant for the winter. 

To overwinter them, dig up their bulbs after blooming and after the first frost. Carefully remove any soil and cut away most of the foliage around the bulbs. Cure them for at least a week, ensuring they’re dry enough for storage.

Once they’re dry, wrap them in a paper bag and store them in a single layer. Ensure your garage doesn’t doesn’t get below freezing during the winter and you’ll have bulbs to plant in spring.  

Dahlia

	botanical name Dahlia pinnata
	sun requirements Full sun
	height 15 inches to 6 feet
	hardiness zones 8-11

Dahlias are popular late summer and fall blooming flowers. There are 42 species and thousands of cultivars to choose from. Some are tall and wispy and others stout and bushy. They are delicate perennials from tropical and subtropical regions. However, if you live in cold climates, you can treat them as annuals and overwinter them in your garage. 

Wait until their foliage turns brown, a few weeks after their blooms have wilted or shortly after the first frost. Be patient and let them send energy into their tuberous roots before trimming them. Carefully dig them up, leaving about 12 inches from their stems. 

Once you’ve dug up the root clumps, place them in a cool, dry space with good air circulation out of direct sunlight. Do this if you expect a freeze. Remove as much soil as you can. Place the root clumps in a wooden bin or container filled with sawdust or peat moss in your garage and check on them throughout the season. If any take on mold or bruising, dispose of them. Once the last threat of frost has passed in spring, replant them in your garden. 

Elephant Ears ‘Thailand Giant’

	botanical name Colocasia gigantea ‘Thailand Giant’
	sun requirements Full sun to partial shade
	height Up to 10 feet
	hardiness zones 8-10

Thailand giants are one of the largest varieties of colocasia elephant ears. They make intense tropical-looking additions to your garden. The easiest way to overwinter these exotic plants in your garage is by storing their tubers. 

Wait until temperatures dip below 40°F (4°C). Carefully dig up your plants’ tubers with a garden fork or shovel, trying not to bruise or damage them in the process. Pull the tubers from the soil and remove any dirt. Check for insects or diseases that could ruin the entire bunch. 

After gently cleaning them, put your tubers in a warm, dry room for a few days to a week (no warmer than 50-60°F or 10-16°C). This helps them prepare for dormancy over winter. When they’re done, place them in a cardboard box with a few ventilation holes and cover them with coco coir. Leave the box in your garage and check on your tubers throughout the winter to make sure they’re still healthy. 

Lantana 

	botanical name Lantana camara
	sun requirements Full sun
	height Up to 6 feet
	hardiness zones 7-11

Lantanas are perennials in warm climates but annuals in cold climates below USDA Hardiness Zone 7. Even if you live in a cold climate, you can try overwintering your lantanas in your garage as long as it doesn’t experience heavy freezes. 

The best way to do this is to wait until the foliage turns brown. Carefully move your plants into a container or pot and cover them with mulch. It is best to grow them in containers anyway, as they can be invasive in various regions of North America. Help encourage them to go dormant by watering them less. 

These bright flowers are harder to overwinter in indoor spaces that experience freezing temperatures. Keep them on shelves, elevated above the floor, and water them sparingly throughout their dormant winter period. If they survive, you’ll have vivid lantana flowers the next season. Replant them in a larger pot with fertilizer and plenty of water the following spring. 

Calla Lily

	botanical name Zantedeschia aethiopica
	sun requirements Full sun to partial shade
	height 2-3 feet
	hardiness zones 8-10

Calla Lilies are tropical-looking perennial flowers that add an elegant touch of white to your garden. In colder climates, you can grow them as annuals and overwinter them in your garage. If the bulbs are healthy and the temperature extremes are not severe, you should be able to grow them again the following season. 

To overwinter them, wait until a week or two before the first frost. Once their foliage turns yellow, cut it down to three inches above the bulbs. Remove all the soil, wash, and let them dry out in a cool, dark space in a container with peat moss or vermiculite. Ensure the area stays around 50-60°F (10-16°C).

After the last threat of frost passes, replant them in a larger pot or container and begin watering them. If the bulbs stay healthy through the winter, you should get robust flowers the following season. 

Dusty Miller 

	botanical name Jacobaea maritima
	sun requirements Full sun to full shade
	height 1-3 feet
	hardiness zones 7-10

Dusty millers are tender perennials that gardeners in cold climates grow as annuals. Their silvery leaves complement any flower garden as a backdrop plant. 

To overwinter dusty millers, transplant them into pots or keep them in their original containers. Move them onto shelves to avoid the coldest air on the ground of your garage. Clip back the foliage to encourage the plant to remain in a dormant state.

During the winter, pick up your pots, and if your plants feel heavy, they’re still healthy. If you notice the soil is dry, give them a little water. After the threat of frost passes, bring your plants outside to re-acclimate them. They can be transplanted with other spring annuals. 

Sweet Potato Vine

	botanical name Ipomoea batatas
	sun requirements Full sun to partial shade
	height 6-10 feet long
	hardiness zones 9-11

Sweet potato vines are the ornamental varieties of the common sweet potato. They give gardens bright green foliage and will even grow indoors. Overwintering your sweet potato vines in your garage is as easy as storing their tubers in your garage. 

Before the first frost, cut your vines down to the ground and carefully dig up their tubers. Remove the soil thoroughly, select the healthiest tubers, and place them in a cardboard box with holes for ventilation. Cover them in peat moss or coco coir and leave them on your garage shelves above the ground for the season. As long as the temperature stays around 50°F (10°C) you’ll have dormant tubers to replant in spring.

Euphorbia ‘Diamond Frost ®’

	botanical name Euphorbia hypericifolia ‘Inneuphdia’ Diamond Frost®
	sun requirements Full sun to partial shade
	height Up to 1.5 feet
	hardiness zones 10-12

Euphorbia ‘Diamond Frost’ ® has gorgeous tiny white bracts that radiate from deep green foliage. They can tolerate plenty of heat and drought, but not cold temperatures. You can overwinter these beautiful plants in your garage by following a few easy steps. 

Before the last chance of frost, transplant your plants in containers and bring them into your garage. Some gardeners prefer to acclimate them to the garage over a few weeks by bringing them indoors at night. These plants will slowly get used to your garage’s temperature and air quality beforehand.