The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Tulsa should be used to estimate when you can plant onions.

Planting Calendar for Onions

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

Onions do well in cold which tells us that you can plant them much earlier than more sensitive plants.

The earliest that you can plant onions in Tulsa 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 fully mature. Starting your onions indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Tulsa. In the coldest months of winter you should expect an average low temperature of 0°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Tulsa and it can change quite a bit from year to year. Half of the time in Tulsa you get surprised by a frost after April 15 so make sure that you are prepared to protect your onions in the event of a surprise late frost.

USDA Zone Info for Tulsa

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Tulsa

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