The USDA Zone info is a great tool for gardeners to help us determine 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 USDA zone info for Highland should be read to determine when it's a good idea to plant asters.

Planting Calendar for Asters

Frost tolerance for asters:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Asters do well in moderate cold which tells us that you can plant them earlier than other frost tender plants.

The earliest that you can plant asters in Highland is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant asters and expect a good harvest is probably September. Any later than that and your asters may not have a chance to grow to maturity. If you are starting your asters indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Highland. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Highland is just an average 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 April 15 so be sure to be ready to protect your asters if you have a surprise late frost.

USDA Zone Info for Highland

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 Highland

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