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.

You will be able to estimate when it's the best time to plant primula by checking out the USDA zone info for Dayton.

Planting Calendar for Primula

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

You can plant primula much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant primula in Dayton 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. You probably don't want to wait any later than that or else your primula may not have a chance to really do well. Starting your primula 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 Dayton. In the coldest months of winter you can expect an average low temperature of -5°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Dayton and it can change quite a bit from year to year. Half of the time in Dayton it frosts late in the year after April 15 so make sure that you are prepared to protect your primula in the event of one of those late frosts.

USDA Zone Info for Dayton

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Dayton

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