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When to Plant Flower-of-an-Hour in San Luis Obispo, CA

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for San Luis Obispo it's a good idea to estimate when it's possible to plant flower-of-an-hour.


Planting Calendar for Flower-of-an-Hour

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

You can plant flower-of-an-hour a bit earlier in the year because they are barely cold tolerant.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant flower-of-an-hour
Possibly ok, but a risky time to plant flower-of-an-hour
Probably not a good time to plant flower-of-an-hour

The earliest that you can plant flower-of-an-hour in San Luis Obispo 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 flower-of-an-hour and expect a good harvest is probably September. Any later than that and your flower-of-an-hour may not have a chance to grow to maturity. Starting your flower-of-an-hour indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in San Luis Obispo. You can expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that USDA zone info for San Luis Obispo may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in San Luis Obispo you get surprised by a frost after February 15 be ready to cover your flower-of-an-hour if you have one of those late frosts.

USDA Zone Info for San Luis Obispo

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 Low25°F
Highest Expected Low30°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 San Luis Obispo

You may be interested in your other planting guides for San Luis Obispo.