The USDA Zone info is a great tool for gardeners to help us estimate 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.

The first chance to plant lobelia in Williston should be figured out by looking at the USDA zone info.

Planting Calendar for Lobelia

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

You can plant lobelia a lot earlier in the year because they do well in cold.

The earliest that you can plant lobelia in Williston 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 lobelia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your lobelia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your lobelia indoors.

Last Frost Date

In Williston the average date of last frost happens on May 15. You should expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Williston is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Williston there is a last frost after May 15 so make sure that you are ready to cover your lobelia in the event of a late frost.

USDA Zone Info for Williston

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Williston

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