When to Plant Thunbergia in Monticello, IL

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. 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 possible to plant thunbergia by checking out the USDA zone info for Monticello.


Planting Calendar for Thunbergia

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

Since thunbergia are not cold tolerant it's important 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 Monticello 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. You probably don't want to wait any later than that or else your thunbergia may not have a chance to grow to maturity. If you are starting your thunbergia 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 April 15 in Monticello. It might get as low as -15°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Monticello and it can change quite a bit from year to year. Half of the time in Monticello it frosts late in the year after April 15 so always be ready to cover your thunbergia if you have one of those late frosts.

USDA Zone Info for Monticello

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°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 -10°F.

Plants to Grow in Monticello

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