When to Plant Calla Lily in Portsmouth, NH

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to estimate when it's the best time to plant calla lily by checking out the USDA zone info for Portsmouth.


Planting Calendar for Calla Lily

Frost tolerance for calla lily: Not tolerant of frost.
When to plant: After all chance of frost has passed.

Since calla lily are not cold tolerant you need to wait until after the last frost before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant calla lily
Possibly ok, but a risky time to plant calla lily
Probably not a good time to plant calla lily

The earliest that you can plant calla lily in Portsmouth is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant calla lily and expect a good harvest is probably August. If you wait any later than that and your calla lily may not have a chance to fully mature. You can get started a little bit earlier by starting your calla lily indoors.

Last Frost Date

In Portsmouth the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Portsmouth is just an average the actual date of last frost changes from year to year. Since half of the time in Portsmouth you get surprised by a frost after April 15 be ready to cover your calla lily if you have one of those late frosts.

USDA Zone Info for Portsmouth

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-10°F
Highest Expected Low-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Portsmouth

You may be interested in your other planting guides for Portsmouth.