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

It's possible to estimate when it's the best time to plant matricaria by using the USDA zone info for Grinnell.

Planting Calendar for Matricaria

Frost tolerance for matricaria:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant matricaria a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant matricaria in Grinnell 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 matricaria and expect a good harvest is probably September. If you wait any later than that and your matricaria may not have a chance to grow to maturity. If you are starting your matricaria indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Grinnell 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.

Since the USDA zone info for Grinnell is just an average the actual date of last frost is different every year. Half of the time in Grinnell last frost occurs after April 15 so make sure that you are ready to cover your matricaria if you have one of those late frosts.

USDA Zone Info for Grinnell

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 Grinnell

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