Friday, May 30, 2014

The spring of our discontent?

It's been a prolonged spring in Massachusetts. Preceded by a long and very cold (near record) winter. Following a hot summer in 2013 with a very large apple crop. Now we're paying the price? I have been asked about the tree fruit crop situation here in Massachusetts. I just want to say it's all over the place, so let me try to explain.

For starters, the 2013 apple crop was a large one, and it was a hot summer. Apples reached the tipping point after several large crop years -- typically biennial apples such as Cameo, Golden Delicious, Goldrush, Honeycrisp and others which bore a large (too large!) crop of fruit in 2013 have a lot of "blanks" (no flower parts, see below) in 2014. And, by-and-large, bloom on other varieties such as McIntosh (our primary variety grown) is variable, but we will have fruit. Macoun looks good, while Cortland bloom was lacking at best? As apple bloom progressed, quite a few flower spurs with malformed buds and/or single blooms were observed -- what the heck? Theories abound, ranging from incomplete/late flower bud development last year, winter injury (although it did not get absolutely cold enough to suspect damage?), an April cold snap when the buds were pushing (although according to critical temperatures, damage should not have occurred)? Quite a few Honeycrisp flowers at the UMass Orchard in Belchertown had just one flower (see below). Apple bloom just did not look good. (Queasy feeling begins.) Although I was pessimistic (as usual, cup is half-empty) I kept thinking it usually turns out better than I expect, and indeed now that we are seeing fruit set (finally) it looks like there is actually potential for a good apple crop here, other than the exceptions already noted. Somewhat interesting, considering how wicked cold the winter was, is the fact we got through bloom with no real frost/freeze threat (except back in early April).
Honeycrisp "blank" flower, 14-May, 2014 at UMass Orchard
Honeycrisp single flower, 14-May, 2014 at UMass Orchard
Let's move on to stone fruit -- peach and cherry. They have not fared so well. A good sign of trouble was mid-winter cold approaching or exceeding -10 F. Damage to flower buds of peach is highly site- and variety-dependent, but begins at -10 F. This spring, it looks like the potential peach crop ranges from no (zero) crop, to maybe what will be a good crop with modest hand-thinning. Some locations/varieties will need very little, if any, hand thinning to produce a decent peach crop. I estimate flower bud damage to range from 100% (again, depending on variety and site) to 50% (maybe lower). I don't think any peach orchard escaped unscathed. Not since 2004 have we lost a peach crop (or partial crop) to mid-winter cold.
Good peach flower bud (top) and bad (winter injured) peach flower bud (bottom)
at UMass Orchard, 5/14/14
Sweet cherry, well, I was pretty pessimistic, but set looks better than I expected. It is, however, variety-dependent. Clearly there was some damage, but I don't have it well-documented. Past history suggests you will start to see sweet cherry bud damage at about the same mid-winter cold temperatures as you see with peach. I want to share one observation, which is confounding but probably fully explainable -- my perception is that you see better bud survival on the weaker wood of peach and cherry, vs. the kind of wood that we would like to think produces the best fruit, i.e., those nice long, pencil-diameter size shoots. I suspect the weaker wood/buds is actually more hardy, having less nitrogen and hardening-off sooner in the late fall to early winter. It might not wake up quite as readily during mid-winter warm-ups too. Kind of frustrating when we attempt to grow "good wood."
Rainier sweet cherry fruit set at UMass Orchard,  5/27/14
Finally, seeing some wood/shoot damage to stone fruit (peach and plum) from presumably the mid-winter cold. It was dry last fall, so going into the winter these trees might have been pre-disposed to damage with a harsh winter.
Winter-damage peach tree in eastern Massachusetts, 29-May, 2014
That is the current situation as I see it -- I will give apples a B+ and stone fruit a C- at this time, however, am not averse to giving them extra credit and improve their grade as the growing season progresses. I constantly have to remind myself as the season goes along that more-and-more fruit suddenly "appears" (don't dismiss chemical thinning of apples!) and that years with a "short crop" are often the most profitable. (As long as you have some fruit!)