One of the best tools that you have as gardeners to help us determine 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 Carroll can be reffered to in order to figure out when it's possible to plant primula.

Planting Calendar for Primula

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

Primula are very cold tolerant which tells us that you can plant them a quite a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant primula in Carroll 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 primula and expect a good harvest is probably September. If you wait any later than that and your primula may not have a chance to grow to maturity. Starting your primula indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Carroll. You can expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Carroll is an average the actual date of last frost will vary from year to year. Since half of the time in Carroll it frosts late in the year after April 15 be ready to cover your primula in the event of a surprise late frost.

USDA Zone Info for Carroll

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Carroll

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