One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when it's a good idea to plant primroses is to examine the USDA zone info for Urbandale.

Planting Calendar for Primroses

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

Primroses are very cold tolerant which tells us that you can plant them much earlier than other plants that might not handle the cold.

The earliest that you can plant primroses in Urbandale 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. Starting your primroses indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Urbandale. It might get as low as -20°F during the coldest months of winter.

Since the USDA zone info for Urbandale is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Urbandale you get surprised by a frost after April 15 be ready to protect your primroses if you have a late frost.

USDA Zone Info for Urbandale

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 Urbandale

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