One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Helena it's possible to determine when it's the best time to plant santolina.

Planting Calendar for Santolina

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

Since santolina are very cold tolerant you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant santolina 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 santolina and expect a good harvest is probably September. Any later than that and your santolina may not have a chance to fully mature. You can get started a little bit earlier by starting your santolina indoors.

Last Frost Date

The average date of last frost is March 15 in Helena. In the coldest months of winter you can expect an average low temperature of 10°F.

Since the USDA zone info for Helena may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Helena last frost occurs after March 15 be ready to protect your santolina in the event of a 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.