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.

A common way of determining when to plant sweet williams is to examine the USDA zone info for Renton.

Planting Calendar for Sweet Williams

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

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

The earliest that you can plant sweet williams in Renton 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 sweet williams and expect a good harvest is probably September. Any later than that and your sweet williams may not have a chance to really do well. You can get started a little bit earlier by starting your sweet williams indoors.

Last Frost Date

On average the last frost is on March 15 in Renton. You can expect an average low temperature of 15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Renton may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Renton last frost occurs after March 15 so make sure that you are ready to protect your sweet williams in the event of a surprise late frost.

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.