The cannas lily is a tall, graceful and striking plant. how to winter canna lilies? Although cannas lilies are perennials, they are very susceptible to frost.
If your cannas lilies are planted in containers, you can move them to a warmer area or grow them as foundation plants near the house and they may not need to be wintered to survive. But if they are planted in the middle of the yard, here are some ways to winterize them to try.
WHY OVERWINTER CANNAS?
canna lilies grow vigorously, forming clumps of thick, fleshy rhizomes that cling to the soil surface. When temperatures reach freezing, there is a lot of plant material to throw away.
Especially when they are easy to dig up, easier to store, and doing so during the winter months allows you to cost-effectively increase their presence in your garden.
You can build your collection of cultivars over time and still have plenty to share with other gardeners.
WHEN SHOULD CANNA LILIES BE DUG UP AND OVERWINTERED?
While canna lilies are sending their tropical foliage skyward during the growing season, they are also spreading into the soil, forming clumps of thick, brittle rhizomes with shallow roots. If you’re north of zone 8, mid-autumn and frost temperatures will signal that it’s time to dig up these rhizomes for winter storage.
The fall garden is a busy one, so don’t add to your workload too early. Let the frost visibly darken the canna lilies tree leaves before you dig – usually in mid to late fall.
The trick is to dig them out of the ground before the temperature drops significantly and the ground freezes. Waiting will also allow you to get the most out of your canna lilies – they will continue to grow, often blooming later in the fall and adding much interest to the fall garden.
Gardeners in zone 7 apply a thick layer of mulch 6-8 inches (15.24-20.32cm) to clumps of canna lilies after cutting down the stems, which are likely to overwinter “in situ”, especially for straight species such as Canna indica. If you have a lot of money and can “afford” to spend some, give it a try!
DIGGING CANNA LILIES
The stems of canna lilies come out of large rhizomes. Most of the rhizomes will be near the surface in the top 10 inches or less.
Occasionally, if they hit a wall or the sides of a pot, the rhizomes will grow downward and can easily bruise or damage the rhizomes, so you need to dig carefully.
You can use a spade or a garden fork. I have used a garden spade when digging canna lilies in large pots.
The first step is to trim the stems about 6 inches (15.24cm) above the roots. This will leave a convenient handle.
If you haven’t used pesticides on your plants and you know your soil is safe, you can try tasting the inside of the stems. (You can serve it in salads)
If I am growing in a pot or trash can, I turn the pot upside down and tap out the entire root if I can.
If canna lilies are growing in the ground or in heavy pots, then I carefully dig them out. I go around the perimeter of the plant and carefully free it from the soil. If you cut the rhizome, don’t worry. Just set any piece aside.
The roots filled the pot so tightly that I had to tap and pull fairly hard.
The second step is to free the rhizomes from the soil. I used my hands mostly. Slowly and gently. You can trim the long fleshy roots, but be careful not to damage or bruise the rhizomes.
PRUNE THE ROOTS OF CANNA LILIES
Once most of the soil has been removed, trim the thicker roots. You can also trim the stems a little shorter.
If the rhizomes are very large, you can carefully break them off into large sections. I do this every year because I usually need smaller rhizomes for potting.
DRYING CANNA LILIES
Canna lilies rhizomes should be allowed to dry out for a few hours. Do not leave them in the sun and do not let them freeze. If the soil is very moist, dry them out until the rest of the soil is almost dry.
This is to prevent your canna lilies from rotting, the roots in this batch were very wet so I didn’t trim them until they had a chance to dry out a bit.
Prepare a large box and have some peat moss ready. I use containers, but if I have wooden boxes or bushel baskets, they will work well too. Place a layer of peat at least 1 inch (2.54 cm) thick at the bottom.
Carefully place a layer of rhizomes on top of the peat, covering them with peat. Put more rhizomes in and cover them. It is important not to let the pieces touch or they may rot. Cover the box with newspaper or plastic that has been cut up.
You want to keep your rhizomes from drying out completely, but you don’t want any condensation. Don’t use play-doh covers. Your roots will rot.
I’ve seen people use newspaper instead of peat moss to wrap the roots.
This is it. Put your container in a dark and cool place. It should be below 50°F (10°C) or Ghana will start to grow too fast, or rot.
I brought my plants in before the first frost and used to keep them in the freezer in the basement. I have moved and lost my freezer.
I now keep them in the workshop. I heat it up enough to keep it above freezing. canna lilies should be cool, but not freezing cold.
I believe the roots can be kept in the freezer if you can make room for them. In this case, it would be useful to wrap them in the thick newspaper.
In the winter, check the roots of your canna lilies to make sure they don’t get moldy from too much condensation.
I have used this method to overwinter my canna lilies for many years. As soon as the weather warms up, they start sprouting and scrambling to plant them.
If you have a sunny window, you can also put them in pots to get them started early.