When to Plant Thunbergia in Mount Vernon, WA

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant thunbergia in Mount Vernon can be estimated by reviewing the USDA zone info.


Planting Calendar for Thunbergia

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

Since thunbergia are not cold tolerant you need to wait until after the last frost has passed before you can plant them.

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

The earliest that you can plant thunbergia in Mount Vernon 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 thunbergia and expect a good harvest is probably August. Any later than that and your thunbergia may not have a chance to fully mature. Starting your thunbergia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Mount Vernon. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for Mount Vernon may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Mount Vernon last frost occurs after March 15 so just be sure to be ready to cover your thunbergia if you have one of those late frosts.

USDA Zone Info for Mount Vernon

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)March 15
Average Date of First Frost (fall)November 15
Lowest Expected Low10°F
Highest Expected Low15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Mount Vernon

You may be interested in your other planting guides for Mount Vernon.