One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

In Riverside you can estimate when it's the best time to plant strawflowers by looking at the USDA zone info.

Planting Calendar for Strawflowers

Frost tolerance for strawflowers:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since strawflowers are one of those plants that can tolerate a tiny bit of cold weather you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

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

The last month that you can plant strawflowers and expect a good harvest is probably September. If you wait any later than that and your strawflowers may not have a chance to fully mature. If you are starting your strawflowers indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Riverside. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Riverside and it will vary from year to year. Since half of the time in Riverside you get surprised by a frost after February 15 be ready to cover your strawflowers if you have a late frost.

USDA Zone Info for Riverside

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 Riverside

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