One of the first steps you take when you are making a decision about 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 USDA zone info for Portsmouth can be looked at to determine when you can plant melampodium.

Planting Calendar for Melampodium

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

Melampodium do not do well in cold weather which tells us that it is necessary to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant melampodium in Portsmouth 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 melampodium and expect a good harvest is probably August. If you wait any later than that and your melampodium may not have a chance to grow to maturity. Starting your melampodium indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on March 15 in Portsmouth. It might get as low as 10°F during the coldest months of winter.

Since the USDA zone info for Portsmouth is just an average the actual date of last frost changes from year to year. Half of the time in Portsmouth there is a last frost after March 15 so just be sure to be ready to cover your melampodium if you have a surprise late frost.

USDA Zone Info for Portsmouth

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Portsmouth

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