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

One way of estimating when to plant lisianthus is to refer to the USDA zone info for Westminster.

Planting Calendar for Lisianthus

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

Lisianthus are not cold tolerant which tells us that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant lisianthus in Westminster 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 lisianthus and expect a good harvest is probably August. If you wait any later than that and your lisianthus may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your lisianthus indoors.

Last Frost Date

The average date of last frost is April 15 in Westminster. You can expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Westminster and it will vary from year to year. Since half of the time in Westminster last frost occurs after April 15 be ready to cover your lisianthus in the event of a surprise late frost.

USDA Zone Info for Westminster

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 Westminster

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