One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Thomson can be used to determine when it's a good idea to plant impatiens.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You should not plant impatiens until after the last frost when the weather gets warmer because they are not cold tolerant.

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

Last Frost Date

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

Just be sure to remember that USDA zone info for Thomson may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Thomson there is a last frost after March 15 so make sure that you are prepared to cover your impatiens in the event of a surprise 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.