One of the best tools that you have as gardeners to help us determine 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.

The USDA zone info for Nashua should be used to estimate when you can plant tithonia.

Planting Calendar for Tithonia

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

It's not a good idea to plant tithonia until after the last frost because they are not cold tolerant.

The earliest that you can plant tithonia in Nashua 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 tithonia and expect a good harvest is probably August. If you wait any later than that and your tithonia may not have a chance to grow to maturity. If you are starting your tithonia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Nashua the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Nashua may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Nashua it frosts late in the year after April 15 be ready to cover your tithonia if you have a surprise late frost.

USDA Zone Info for Nashua

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 Nashua

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