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.

You will be able to figure out when it's the best time to plant impatiens by looking at the USDA zone info for Highland.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After the last frost.

Since impatiens require warm weather you need to wait until after the last frost before you can plant them.

The earliest that you can plant impatiens in Highland 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 impatiens and expect a good harvest is probably September. If you wait any later than that and your impatiens may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your impatiens indoors.

Last Frost Date

The average date of last frost is February 15 in Highland. It might get as low as 25°F during the coldest months of winter.

Keep in mind that USDA zone info for Highland is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Highland it frosts late in the year after February 15 so just be sure to be ready to protect your impatiens if you have a surprise late frost.

USDA Zone Info for Highland

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

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

Plants to Grow in Highland

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