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

The USDA zone info for Helena should be reviewed to determine when it's possible to plant stoneseed.

Planting Calendar for Stoneseed

Frost tolerance for stoneseed:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Stoneseed require warm weather which tells us that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant stoneseed in Helena 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 stoneseed and expect a good harvest is probably August. You probably don't want to wait any later than that or else your stoneseed may not have a chance to really do well. If you are starting your stoneseed indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Remember that USDA zone info for Helena is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Helena last frost occurs after March 15 be ready to cover your stoneseed in the event of a surprise late frost.

USDA Zone Info for Helena

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°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 15°F.

Plants to Grow in Helena

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