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

You should be able to figure out when it's the best time to plant basil by using the USDA zone info for Renton.

Planting Calendar for Basil

Frost tolerance for basil:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You can not plant basil until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant basil in Renton is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant basil and expect a good harvest is probably August. Any later than that and your basil may not have a chance to fully mature. Starting your basil indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is March 15 in Renton. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Renton is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Renton you get a frost after March 15 so just be sure to be ready to cover your basil if you have one of those late frosts.

USDA Zone Info for Renton

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Renton

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