Is it Too Late to Plant Calla Lily? 3 Important Notes

No matter whether you live in warmer or cooler climates, you can enjoy the tropical Calla Lily flower. The Grow Monster has always thought this an interesting flower, and while it may take more work than your usual spring perennials you can plant Calla Lily to give extra interest to a sunny spot in your garden. There are many different colors of Calla Lily, choose your favorite or try something new in your garden this year!

Is it too late to plant Calla Lily? Calla Lily must be planted in the spring after any threat of frost in loose, well-draining soil.

The following important notes will help you grow beautiful, healthy Calla Lily flowers for years to come:

1. Plant Calla Lily rhizomes in the spring after any threat of frost has passed.
2. Find a sunny to partial shade spot, especially in colder growing zones since Calla Lily is a tropical plant.
3. Calla Lily rhizomes should be planted in loose, well-draining soil that will not stay soggy.

You can enjoy Calla Lilies in your garden space or as part of a cut flower garden to display indoor in vases. If you’d like to try growing this tropical plant, read on to find out what times of year are the best to plant Calla Lily.

When Should You Plant Calla Lily?

Calla Lily should be planted in the spring after all threat of frost has passed in your area. Since Calla Lily is a tropical plant, they are winter hardy in zones 8-10, but can also overwinter in some milder zone 7 locations. You can check your growing zone at the USDA website by inputting your zip code. They do not do well in temperatures lower than 50 F (10 C). Calla Lily plants prefer temperatures between 60-80 F (15.5- 26.7 C), otherwise you will need to dig them up each year and replant again in spring when the temperatures are warm again.

To ensure you plant Calla Lily at the right time in the spring, check when your last frost will be. If you don’t know when you average last frost date is, you can look on the map below from NOAA. You will want to wait until the temperatures are warm enough before you plant Calla Lily otherwise you risk losing them.

Calla Lily rhizomes need to be kept dry if storing over the winter months. Sometimes, people refer to these plants as bulbs in a more general term, but they are actually rhizomes which is a continuous growing long stem-like structure that will put off roots and reproduce as offshoots at various intervals. These rhizomes should be planted at a depth of about 2- 4 inches leaving enough space between plants for this lateral growth. Water them in well but don’t create any puddles because you risk the Calla Lily rotting.

There have been experiments with Calla Lily bulbs to determine which temperatures allow them to grow best. One study suggests that Calla Lily will be larger, longer, and healthier at higher temperatures and will produce flowers for a longer period of time. This is why we want to make sure to plant Calla Lily at the correct temperatures. Calla Lily will flower in summer through late fall, and even in winter in the warmer climates. One study suggests you will get larger and healthier plants by letting them grow 2 cycles followed by a larger rest cycle in storage.

What Happens if You Plant Calla Lily Too Early?

Because Calla Lily does well in warmer temperatures, at least 55 F (12.7 C), your Calla Lily may not survive if planted too early. For some areas, you will be able to plant Calla Lily as early as March while other zones will need to wait until May for the temperatures to be warm enough to plant the rhizomes outdoors. This also means that you will need to dig them up at different times as the temperatures decrease in the fall and winter months depending on your growing zone.

If you are having a milder winter, you should still wait to plant the Calla Lily until your average last frost date has passed. If you do plant them and there is frost the Calla Lily rhizomes may not survive. There are a few things you can do to try to save the Calla Lily rhizomes from frost damage. You could put a heavy layer of mulch to help insulate the ground and if you don’t have mulch can use blankets with rocks on top or other garden soil. The goal is to keep the ground temperature warmer while the outside temperatures are so low.

Can You Plant Calla Lily in Winter?

If you live in a zone colder than zone 8 you will not be able to plant Calla Lily in winter. If you are in an area that does not get winter frost, you can plant the Calla Lilies at any time (typically zones 8-11). Zone 7 may be able to plant Calla Lily in winter if you take extra measures to protect the bulbs from any hard freeze you will receive. This includes digging them a bit deeper, adding extra soil or mulch on top of the area where the rhizomes are, or putting a hoop house or cloche over the area where the Calla Lily is planted.

While you shouldn’t plant Calla Lily rhizomes in the winter in colder zones, you can overwinter them with a few caveats. Calla Lily can survive temperatures as low as 50 F (10 C). If they are in pots, just move the pots indoors to your garage or basement. If the rhizomes are in the ground, you will need to add 4-6 inches of mulch on top to try to keep the ground warm enough over the winter.

When the temperatures are warmer and all threat of frost is gone, you can remove the mulch. Take a look at the Calla Lily roots to determine if the plant is still healthy. White roots mean you successfully overwintered them, whereas black or brown roots mean the plant has succumbed to the freezing temperatures. Overall, if you live in an area that freezes in winter, it is not a good idea to plant Calla Lily in winter.

Can You Plant Calla Lily in Fall?

If you live in zones 9-11, you can plant Calla Lily anytime including the fall. However, if you live in colder zones the fall is when you will want to dig up your Calla Lily rhizomes, split any that are getting too large, and store them in a dry location. You will know when to dig up the Calla Lily once the leaves have all turned yellow and you’ve had your initial fall frost. This can vary depending on which zone you are in but generally happens sometime in the fall. It is important to dig up the rhizomes because any temperatures lower than 25 F (-3.8 C) will damage them and potentially kill your plants.

When you see the leaves on your Calla Lily turn yellow that means the plant has gone dormant. Once the plant is dormant, it is safe to dig them up to store and replant in the spring once all threat of frost has gone. You will want to clear all the dirt from the roots and let the rhizomes dry overnight and then place in a ventilated paper bag or cardboard box so they aren’t susceptible to rot or come in contact with moisture while in storage. Studies show bacterial rot will develop when the rhizomes are stored with little or no ventilation.

Can You Plant Calla Lily in Summer?

Calla Lily generally begin blooming in late spring through summer and even fall in most zones. They can start flowering as early as June. Summer is a great time to put Calla Lily in pots right before July so you will have lovely flowers throughout the hotter summer months when many other bulbs have already run their course. Plant the Calla Lily in full sun or partial shade if in warmer climates. It is best to plant the rhizomes in the spring, but you can wait until early summer and still have enough time for flowering.

If you plant your Calla Lily with other plants that need more even watering during the hot summer months, remember that the Calla does not want to sit in standing water for too long or it could start to rot. One idea is to intersperse them with other bulbs to create a garden space that will be flowering the entire year. By planting them with other bulbs that do not like to stay wet you can better control the amount of moisture in the soil in that area of the garden. You could also stagger their planting from earlier in spring through summer to always have plants starting to bloom at different times.

Final Thoughts

While the Calla Lily is a tropical plant, you can enjoy them even in cooler climates as long as you dig them up to store during the winter months. Even though it is ideal to plant Calla Lily in the spring, it will not be too late to plant Cally Lily in summer for most zones. You should only plant Calla Lily if there is no threat of frost and it can be grown year-round in the warmer zones 8-11. At The Grow Monster, we enjoy creating garden spaces that appear to change color throughout the seasons as different plants are in bloom.

Read more about creating a Pollinator Garden in the spring along with Calla Lily to create a welcoming garden space in your yard.