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.

The earliest that you can plant onions in Grimes can be determined by checking out the USDA zone info.

Planting Calendar for Onions

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

You can plant onions much earlier in the year because they do well in cold.

The earliest that you can plant onions in Grimes 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 onions and expect a good harvest is probably September. Any later than that and your onions may not have a chance to really do well. If you are starting your onions indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Grimes. You should expect an average low temperature of -20°F in the coldest months of winter.

Always keep in mind that USDA zone info for Grimes is an average and the actual date of last frost will vary from year to year. Half of the time in Grimes you get surprised by a frost after April 15 so just be sure to be ready to cover your onions if you have one of those late frosts.

USDA Zone Info for Grimes

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 Grimes

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