One of the best tools that you have as gardeners to help us estimate 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.

You will be able to determine when it's possible to plant achimenes by using the USDA zone info for Jefferson.

Planting Calendar for Achimenes

Frost tolerance for achimenes:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Achimenes require warm weather which tells us that it is necessary to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant achimenes in Jefferson 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 achimenes and expect a good harvest is probably August. Any later than that and your achimenes may not have a chance to grow to maturity. If you are starting your achimenes indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Jefferson the average date of last frost happens on April 15. You should expect an average low temperature of -20°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Jefferson and it is different every year. Since half of the time in Jefferson you get surprised by a frost after April 15 be ready to protect your achimenes in the event of a surprise late frost.

USDA Zone Info for Jefferson

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 Jefferson

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