When to Plant Onions in Plano, IL

One of the first steps you take when you are figuring out your gardening schedule is find your 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.

One way of figuring out when it's a good idea to plant onions is to consult the USDA zone info for Plano.

Create beautiful hand-made plants at forever-plants.com

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

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant onions
Possibly ok, but a risky time to plant onions
Probably not a good time to plant onions

The earliest that you can plant onions in Plano 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. You probably don't want to wait any later than that or else your onions may not have a chance to grow to maturity. You can get started a little bit earlier by starting your onions indoors.

Last Frost Date

In Plano the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Plano and it changes from year to year. Since half of the time in Plano you get surprised by a frost after April 15 be ready to cover your onions in the event of one of those late frosts.

USDA Zone Info for Plano

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 Plano

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