One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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 reviewing the USDA zone info for Thomson you will be able to figure out when it's possible to plant nierembergia.

Planting Calendar for Nierembergia

Frost tolerance for nierembergia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You should not plant nierembergia until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant nierembergia in Thomson is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant nierembergia and expect a good harvest is probably August. Any later than that and your nierembergia may not have a chance to grow to maturity. Starting your nierembergia indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Thomson and it changes from year to year. Since half of the time in Thomson last frost occurs after March 15 be ready to cover your nierembergia in the event of a late frost.

USDA Zone Info for Thomson

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 Thomson

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