The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. 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 Gretna should be looked at to figure out when to plant primroses.

Planting Calendar for Primroses

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

Primroses do well in cold which tells us that you can start planting them much earlier than plants that are more sensitive to the cold.

The earliest that you can plant primroses in Gretna 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 primroses and expect a good harvest is probably September. If you wait any later than that and your primroses may not have a chance to grow to maturity. You can get started a little bit earlier by starting your primroses indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Gretna and it changes from year to year. Half of the time in Gretna you get a frost after April 15 so just be sure to be ready to cover your primroses in the event of a surprise late frost.

USDA Zone Info for Gretna

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 Gretna

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