When can I plant Helianthemum in Zone 5a

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.

The USDA zone info for Zone 5a should be looked at to determine when it's possible to plant helianthemum.


Planting Calendar for Helianthemum

Frost tolerance for helianthemum: Tolerant of some frost.
When you should plant them: Up to 5 weeks before last frost.

Helianthemum do well in moderate cold which means that you can plant them earlier than more sensitive plants.

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

The earliest that you can plant helianthemum in Zone 5a is February. However, you really should wait until March if you don't want to take any chances.

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

Last Frost Date

The average date of last frost is April 15 in Zone 5a. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Zone 5a may not be accurate from year to year our actual date of last frost can change quite a bit from year to year. Half of the time in Zone 5a it frosts late in the year after April 15 so make sure that you are prepared to protect your helianthemum if we have one of those late frosts.

USDA Zone Info for Zone 5a

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Zone 5a

You may be interested in our other planting guides for Zone 5a.