One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant sedum in Helena should be figured out by using the USDA zone info.

Planting Calendar for Sedum

Frost tolerance for sedum:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Sedum are one of those plants that can tolerate quite a bit of cold weather which means that you can plant them a quite a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant sedum in Helena 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 sedum and expect a good harvest is probably September. Any later than that and your sedum may not have a chance to fully mature. Starting your sedum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on March 15 in Helena. In the coldest months of winter you can expect an average low temperature of 10°F.

Always keep in mind that USDA zone info for Helena is not always accurate and the actual date of last frost is different every year. Half of the time in Helena there is a last frost after March 15 so make sure that you are prepared to protect your sedum in the event of one of those late frosts.

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.