The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for London can be looked at to figure out when it's the best time to plant lobelia.

Planting Calendar for Lobelia

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

Lobelia are one of those plants that can tolerate quite a bit of cold weather which tells us that you can get them planted much earlier than other frost tender plants.

The earliest that you can plant lobelia in London 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 lobelia and expect a good harvest is probably September. Any later than that and your lobelia may not have a chance to really do well. If you are starting your lobelia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in London. In the coldest months of winter you should expect an average low temperature of -5°F.

Remember that USDA zone info for London is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in London it frosts late in the year after April 15 be ready to cover your lobelia if you have one of those late frosts.

USDA Zone Info for London

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in London

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