Even though I turned 39 a couple of days ago, I dont want to sound like the old curmudgeon.
You all know the one or are the one who scoffs when people complain about the weather: I remember when April was considered winter, or If you plan on planting your garden on Mothers Day, then plan on replanting it on Fathers Day.
I would have to say that this last April (and so far the first week of a snowy May) was one of the most unappealing and forgettable springs on recent record. After a lovely but dry March got us all excited about the garden and landscape, April literally blew in some crummy weather. The winds were relentless (multiple days with gusts over 40 mph), the precipitation was sporadic, the skies especially on the weekends were gray, and to top it all off, the last week of April was quite cold.
Typically, these cold temperatures shouldnt affect the cold-season vegetable crops that may have been planted earlier in the month. However, fruit tree blossoms dont tolerate temperatures below 30 degrees very well.
b Apple trees: Around the county the majority of apple trees have been starting to bud over the last week. Depending on your microclimate, the blossom could be in a tight cluster or in full bloom. Either way, the blossoms can withstand temperatures as low as 27 to 28 degrees for 30 minutes without damage.
b Pear and plum trees: Again, depending on the microclimate, the blossoms could be in a wide range of stages. Most are at full bloom or just past. If the tree is in full bloom, then the tree is more susceptible to damage as the minimum temperature gets closer to 28 to 29 degrees. If you are past bloom, your tree is more likely to have decent fruit production (unless the frigid winter temperatures killed off lots of the trees flower buds or if pollinators for trees that need cross-pollination werent active) this year.
b Plum trees: See description above for pears.
b Other stone fruits: Apricots, cherries and peaches also fall in the similar range as the pome (apples and pears) fruit, with damage to buds occurring when temperatures get below 27 degrees.
In order to add to the confusion or complexity of the situation, fruit trees tend to flower at different times during the spring months. In general and I cannot reiterate the word general enough the order in which fruit trees flower is: apricots, peaches, sweet cherries (notice that we tend to see years without fruit on these three trees?), pears and plums, tart cherries and then apples.
However, with the vast amount of cultivars of trees (there are over 7,500 cultivars of apples alone) we see widely different flowering periods. For example, there are peaches that flower late and apples that tend to flower early.
So although we had a recent string of cold nights, your trees flowers may be fine. The cold temperatures may have actually thinned the tree, leaving you with big red apples in the fall. Just in time for the teachers desk.
email@example.com or 382-6464. Darrin Parmenter is director and horticulture agent of the La Plata County Extension Office.