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When to Plant Alternaria in Portola Valley, CA

One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to determine when it's the best time to plant alternaria by using the USDA zone info for Portola Valley.


Planting Calendar for Alternaria

Frost tolerance for alternaria: Not tolerant of frost.
When to plant: After the last frost has passed.

Alternaria do not do well in cold weather which means that you need to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

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

The earliest that you can plant alternaria in Portola Valley 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 alternaria and expect a good harvest is probably September. You probably don't want to wait any later than that or else your alternaria may not have a chance to grow to maturity. Starting your alternaria indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Portola Valley. It might get as low as 30°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Portola Valley and it can change quite a bit from year to year. Half of the time in Portola Valley last frost occurs after January 31 so always be ready to cover your alternaria if you have a surprise late frost.

USDA Zone Info for Portola Valley

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)January 31
Average Date of First Frost (fall)December 15
Lowest Expected Low30°F
Highest Expected Low35°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 35°F.

Plants to Grow in Portola Valley

You may be interested in your other planting guides for Portola Valley.