When to Plant Tall Phlox in Zone 1a

The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant tall phlox in Zone 1a can be estimated by checking out the USDA zone info.


Planting Calendar for Tall Phlox

Frost tolerance for tall phlox: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Since tall phlox are moderately cold tolerant you can plant them a bit earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant tall phlox
Possibly ok, but a risky time to plant tall phlox
Probably not a good time to plant tall phlox

The earliest that you can plant tall phlox in Zone 1a is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant tall phlox and expect a good harvest is probably July. Any later than that and your tall phlox may not have a chance to really do well. You can get started a little bit earlier by starting your tall phlox indoors.

Last Frost Date

In Zone 1a the average date of last frost happens on June 15. In the coldest months of winter you can expect an average low temperature of -60°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Zone 1a and it is different every year. Since half of the time in Zone 1a last frost occurs after June 15 be ready to protect your tall phlox if you have a late frost.

USDA Zone Info for Zone 1a

Here is the info for USDA Zone 1a.

Average Date of Last Frost (spring)June 15
Average Date of First Frost (fall)July 15
Lowest Expected Low-60°F
Highest Expected Low-55°F

This means that on a really cold year, the coldest it will get is -60°F. On most years you should be prepared to experience lows near -55°F.

Plants to Grow in Zone 1a

You may be interested in your other planting guides for Zone 1a.