When can I plant Thyme in Zone 4a

Before planting it is a good idea to find our USDA Zone info to determine our garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for our area.

You can estimate when it's the best time to plant thyme in Zone 4a by referring to the USDA zone info.


Planting Calendar for Thyme

Frost tolerance for thyme: Very tolerant of frost.
When you should plant them: Up to 7 weeks before last frost.

You can plant thyme earlier in the year because they are very cold tolerant.

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

The earliest that you can plant thyme in Zone 4a is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant thyme and expect a good harvest is probably August. If you wait any later than that and your thyme may not have a chance to really do well. Starting your thyme indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Zone 4a. In the coldest months of winter we should expect an average low temperature of -30°F.

Remember that our actual date of last frost is just an average because it is based on the USDA zone info for Zone 4a and it will vary from year to year. Since half of the time in Zone 4a there is a last frost after May 15 be ready to protect your thyme in the event of one of those late frosts.

USDA Zone Info for Zone 4a

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-30°F
Highest Expected Low-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Zone 4a

You may be interested in our other planting guides for Zone 4a.