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.

You will be able to determine when it's a good idea to plant purple bell vines by looking at the USDA zone info for Sterling.

Planting Calendar for Purple Bell Vines

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

You can plant purple bell vines slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant purple bell vines in Sterling 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 purple bell vines and expect a good harvest is probably August. You probably don't want to wait any later than that or else your purple bell vines may not have a chance to fully mature. If you are starting your purple bell vines 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 Sterling. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Sterling is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Sterling it frosts late in the year after April 15 be ready to cover your purple bell vines if you have one of those late frosts.

USDA Zone Info for Sterling

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Sterling

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