When to Plant Lobelia in Zone 3b

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.

The first chance to plant lobelia in Zone 3b should be estimated by looking at the USDA zone info.


Planting Calendar for Lobelia

Frost tolerance for lobelia: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Lobelia do well in cold weather which means that you can plant them earlier in the year than other plants that might not handle the cold.

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

The earliest that you can plant lobelia in Zone 3b is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant lobelia and expect a good harvest is probably August. If you wait any later than that and your lobelia may not have a chance to grow to maturity. Starting your lobelia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Zone 3b the average date of last frost happens on May 15. It might get as low as -35°F during the coldest months of winter.

Keep in mind that USDA zone info for Zone 3b is just an average and the actual date of last frost changes from year to year. Half of the time in Zone 3b you get surprised by a frost after May 15 so make sure that you are prepared to protect your lobelia in the event of a late frost.

USDA Zone Info for Zone 3b

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-35°F
Highest Expected Low-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Zone 3b

You may be interested in your other planting guides for Zone 3b.