As we creep towards strawberry planting season on the Central Coast, it is always good to review where we stand currently on nursery cold conditioning, and with this in mind, think about adjustments to the post harvest supplementary chill based on what sort of winter we might be expecting.
Those of you who know me understand my faith in hedging my bets and planning for contingencies. I favor decisions with a high probability of success and decent outcomes over swing for the fences with blow your socks off results but missing and failing most of the time. Short supplemental chill times with early planting dates to get the beat on the competition are not my thing since this strategy puts good plant vigor at risk, especially if this 2017-18 winter is warm.
Chill accumulation for this year looks good at the nurseries up at MacDoel. Using Lassen Canyon Nursery's chill accumulation chart (also appreciate the comps to previous years- very useful), shows that, after a warm start in September, hours have really ramped up and currently as of October 5 we are at 337 total hours according to my Utah model calculations (which subtracts chill during warm weather episodes, and discounts temperatures under freezing - look elsewhere on this blog for how I am doing this). That compares very well with previous years, and is in fact ahead of many of them.
Further, looking forward to what sort of winter we are to expect, let's go to the NOAA weather maps. Quite simply, for all of our strawberry production areas, it is as of now 40% probable that we get temperatures above normal this winter (being December, January and February). This is up from 33% a few weeks ago, so I am sensing a trend which seems to confirm where we are headed.
In conclusion, with solid field chill already in the can but a good probability of a warmer than normal winter in the offing, I would again this year favor just a little bit more supplemental chill than customary.
Attached is the latest iteration of the grower guidelines a number of us at UC Cooperative Extension have written and have had published by the California Strawberry Commission.
Super timely since planting is right around the corner, this piece on anthracnose in strawberry caused by the pathogen Colletotrichum , was written by myself, Steven Koike and Oleg Daugovish. It was then reviewed by our strawberry science colleagues Gerald Holmes, Kelly Ivors and Jenny Broome. Translation into Spanish (attached below) done by the Commission's Ariel Zajdband into pitch perfect Spanish in a single hour. The Commission's Joy Jacobs kept the project moving and she and Mercy Olmstead brought it over the finish line.
I'm really very proud of this team effort to put the latest settled science on a serious disease into the hands of growers, PCA's and industry people. I am privileged to work with such a great team of people!
I've had this forwarded to me a bunch of times over the past few days, and finally did have a chance to read the whole thing. Although I trend more towards the meat and potatoes fare of the Wall Street Journal, it's always a pleasure to read the beautiful mastery of English on tap at the New Yorker magazine.
I wouldn't say the title is quite congruent with the content, since the UC program plays a huge role in the story as well.
Final comment without getting into too much detail, is that while the author did a really good job of writing, some of the opinions shared with her (yes, opinions) don't agree with what I believe.
Since digging for strawberry plants destined for Salinas and Watsonville started at Macdoel just a few days ago, I thought it would be judicious to have a look at how many chill hours we've accumulated so far and what it means for additions to supplemental chill, especially for our day neutral varieties.
I checked with the Lassen Canyon nursery chill accumulator here: http://lassencanyonnursery.com/cumulative-chilling-hours-and-weather-conditions/ .
Looking at the data for Oct 18 of this year and running my calculations via the Utah model (which subtracts chill hours for temperatures realized above 60oF, see previous posts), we have currently accumulated 325 units of chill. Given that last year's chill accumulation was 164 units and by most commentator's opinion a decent accumulation, 325 accumulated chill units this year is very satisfactory.
So what does this mean for adjustments on supplemental chill? Personally, I think growers may want to take the strong field chill in stride, and now look forward to what sort of winter we are going to have. Looking at the NOAA data, we are probably in for a weak “La Niña” system this year, which according to the “Color Outlook Maps” for temperature, we have something like a 40% chance of having slightly warmer than normal temperatures in November, December and January.
The question then is what sort of adjustment should or needs to be made to supplemental chill. It's actually not an easy question to answer, given the strong field chill. Then again the odds of a slightly warmer than normal winter would give me some reason to err on the side of caution and go a tad longer than customary on the supplemental chill ./span>
Article out of this morning's Wall Street Journal. Apparently American consumers are going wild over knobbled carrots, weird apples and mis-shapen potatoes.
Consumers, we have a deal for you! Catfaced strawberry fruit and poorly pollinated blackberries we can deliver by the pallet. Step right up!
Seriously, this is something pretty intriguing.