One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for South Portland it's possible to figure out when to plant salpiglossis.

Planting Calendar for Salpiglossis

Frost tolerance for salpiglossis:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You really shouldn't plant salpiglossis until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant salpiglossis in South Portland 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 salpiglossis and expect a good harvest is probably August. If you wait any later than that and your salpiglossis may not have a chance to fully mature. You can get started a little bit earlier by starting your salpiglossis indoors.

Last Frost Date

The average date of last frost is April 15 in South Portland. You can expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for South Portland is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in South Portland last frost occurs after April 15 so always be ready to cover your salpiglossis in the event of a late frost.

USDA Zone Info for South Portland

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 South Portland

You may be interested in your other planting guides for South Portland.