When to Plant Osteospermum in Zone 1b

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. 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 a good idea to plant osteospermum in Zone 1b by using the USDA zone info.


Planting Calendar for Osteospermum

Frost tolerance for osteospermum: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

Osteospermum tend to make it in mild cold which means that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

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

The earliest that you can plant osteospermum in Zone 1b 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 osteospermum and expect a good harvest is probably July. If you wait any later than that and your osteospermum may not have a chance to grow to maturity. If you are starting your osteospermum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Zone 1b the average date of last frost happens on June 15. It might get as low as -55°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Zone 1b and it changes from year to year. Half of the time in Zone 1b it frosts late in the year after June 15 so make sure that you are ready to cover your osteospermum in the event of a surprise late frost.

USDA Zone Info for Zone 1b

Here is the info for USDA Zone 1b.

Average Date of Last Frost (spring)June 15
Average Date of First Frost (fall)July 15
Lowest Expected Low-55°F
Highest Expected Low-50°F

This means that on a really cold year, the coldest it will get is -55°F. On most years you should be prepared to experience lows near -50°F.

Plants to Grow in Zone 1b

You may be interested in your other planting guides for Zone 1b.