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

It's a good idea to figure out when it's possible to plant lithospermum by reviewing the USDA zone info for Ripon.

Planting Calendar for Lithospermum

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

Since lithospermum require warm weather it's important to wait until after the last frost before you can plant them.

The earliest that you can plant lithospermum in Ripon is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant lithospermum and expect a good harvest is probably September. If you wait any later than that and your lithospermum may not have a chance to grow to maturity. 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 is on February 15 in Ripon. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Ripon is just an average the actual date of last frost changes from year to year. Half of the time in Ripon last frost occurs after February 15 so make sure that you are prepared to cover your lithospermum in the event of a surprise late frost.

USDA Zone Info for Ripon

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

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

Plants to Grow in Ripon

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