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When to Plant Lithospermum in Iron Mountain, MI

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 Iron Mountain can be reviewed to determine when you can plant lithospermum.


Planting Calendar for Lithospermum

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

Lithospermum are not cold tolerant which tells us that you need to wait until it warms up after the last frost before you can plant them.

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 Iron Mountain is May. However, you really should wait until June 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. You probably don't want to wait any later than that or else 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

The average date of last frost is May 15 in Iron Mountain. In the coldest months of winter you can expect an average low temperature of -30°F.

Always keep in mind that USDA zone info for Iron Mountain is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Iron Mountain it frosts late in the year after May 15 so make sure that you are ready to protect your lithospermum in the event of a late frost.

USDA Zone Info for Iron Mountain

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-30°F
Highest Expected Low-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Iron Mountain

You may be interested in your other planting guides for Iron Mountain.