I'm in San Luis Obispo and our last frost date is March 15th. My mom is in Santa Cruz and she said its about the same there. I think there are always those freak, outside chances that you could get frost after that, but it is highly unlikely.

Micro climates change everything. I'm in the Santa Clara Valley (Sunnyvale) and I go to Weather Bug and can see the difference in temps recorded from 2 miles in one direction to 2 miles in the opposite direction. I suggest you get a thermometer and record the nighttime lows in the spot where you plan to plant...but then that will also be only a yearly average. We get a killing freeze about every 9 or 10 years, and the rest of the time things are okay. Sunset paints with a broad brush, but they are much more detailed than most other maps.

I recently went looking for the chill hours for Santa Clara county, and NONE are recorded. I e-mailed the fruits and nuts at davis edu, and they don't have the info either.

I can plant tomatoes here on the south side of my house against the white stucco on April 1st. Elsewhere in my yard they won't get enough heat that early, so there are even micro climates on my little chunk of real estate.

Good Luck!

-Babka

As unbelievable as it may seem, last frost dates here in Humboldt County are 5/15, although there is plenty that can be put in before that which will survive light frosts such as we get in later Spring.

Can't grow tomatoes or other hot weather veggies here AT ALL because of the proximity of the ocean and also the foggy summers (I tried beans, eggplant, corn and tomatoes early on in my time here and it was very, very sad.) Have had some luck with those crops a 1/4 mile more inland and with some altitude thrown in so, yes, micro-climates make all the difference.

When considering last frost dates keep in mind those are an AVERAGE last frost date. Gardeners are always taking a risk that a late frost may occur well beyond the average date. As for chilling hours, those are hours below 45 degrees and the Santa Clara valley before it was paved has a long history as a fruit growing area. You county UCCE extension can give you the average as well as the year to date of chilling hours. Al

Al- I went there and here's what I got...no info posted since last Oct. The same outpost does the chill hours for the Pomology report. Someone must've removed their funding.

-Babka

Here is a link that might be useful: No numbers since last Oct.

Correction: Actually there is no info since April of 2008. Someone was at least posting the "zeros"for a while. I'm just a home gardener. Where do the orchard growers (there are a few left in the Santa Clara valley, I think) go to get this info. I can get local highs and lows, but not chill hours.

-Babka

babka they may not be posting on a website but I think they have them at the local Santa Clara office. Have you telephoned them? Al

Al-

Thanks. I didn't even think about calling locally as I just figured this info would be available on-line. I e-mailed the folks at the California Pomology website, and the pomology person at UC Davis responded by copying me on an e-mail to the Monterey fellow, asking why nothing is posted. I'll take your advice and do it the old fashioned way and pick up a phone and see what I can find out that way.

I don't have fruit trees, but rather a collection of hostas that need those chill hours. I thought it would be interesting to have the chill hours to compare over the years with regard to how the hostas thrive or dwindle.

Thanks,

-Babka

Here is a link that might be useful: Pomology Weather