The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Alpine you can figure out when it's possible to plant delphinium by using the USDA zone info.

Planting Calendar for Delphinium

Frost tolerance for delphinium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Delphinium can survive in mild cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant delphinium in Alpine 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 delphinium and expect a good harvest is probably August. If you wait any later than that and your delphinium may not have a chance to fully mature. If you are starting your delphinium indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Alpine. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Alpine is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Alpine there is a last frost after April 15 be ready to protect your delphinium if you have a late frost.

USDA Zone Info for Alpine

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Alpine

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