When to Plant Lithospermum in Allentown, PA

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.

You can determine when it's the best time to plant lithospermum in Allentown by checking out the USDA zone info.


Planting Calendar for Lithospermum

Frost tolerance for lithospermum: Not tolerant of frost.
When to plant: After the last frost has passed.

You really shouldn't plant lithospermum until after the last frost because they require warm weather.

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

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

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Allentown. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Allentown is just an average the actual date of last frost is different every year. Since half of the time in Allentown last frost occurs after April 15 be ready to protect your lithospermum in the event of a late frost.

USDA Zone Info for Allentown

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 Low0°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 Allentown

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