One of the best tools that you have as gardeners to help us figure out 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.

You should be able to determine when you can plant heliotrope by checking out the USDA zone info for Renton.

Planting Calendar for Heliotrope

Frost tolerance for heliotrope:	Not tolerant of frost.
When to plant:	After the last frost.

You can not plant heliotrope until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant heliotrope 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 heliotrope and expect a good harvest is probably August. If you wait any later than that and your heliotrope may not have a chance to grow to maturity. If you are starting your heliotrope indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Renton. In the coldest months of winter you can expect an average low temperature of 15°F.

Just be sure to remember that USDA zone info for Renton is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Renton you get surprised by a frost after March 15 be ready to protect your heliotrope 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.