If I Have Peach Blooms Now- I'll Have Fruit...Right?

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After that brutal punch of cold weather ripping through Northeast Ohio this past December 23rd through December 27th, inquiring minds want to know if we’ll have peaches.  How cold it was that night depends upon location, but official records indicate that Cleveland, Ohio dropped from the daytime high of 43°F to -4°F on the 23rd !!  Then on December 24th the daytime high was 13°F and the low that night was -1°F!!  There were two nights in January that had lows of 16°F, followed by two nights in February with lows of 12°F and one night in March with a low of 18°F.  So, will we have fresh tree-ripened peaches in Northeast Ohio this year? I’ll predict that we’ll have peaches but just what percent of a full crop depends on many factors.


Viable peach buds beginning to expand
L to R types of peach buds- Winter damaged bud; expanding vegetative bud; and viable fruit bud



Peach branch with both winter damaged and viable fruit buds; Note: overall number of buds damaged
Peach branch showing winter damaged and viable fruit buds; NOTE overall number of winter damaged buds


One of the tests used to determine if the peach crop has been damaged or not is to go into the orchard and cut some buds.  This method is simple, fast and easy to determine if the peach crop was damaged by the winter weather conditions.  Typically, we wait to test buds until most of the winter weather is over, like around mid-March.  Just take a razor blade and slice longitudinally through several buds on various peach branches.  Keep track of the total number tested and how many still contain nice green and white tissue inside.  This will give you the percentage of bud loss and the potential impact on the peach crop.  If the bud tissue is yellow or brown or dried out, then that bud is dead.


Viable peach bud cut open showing live green & white tissue
Viable peach bud cut open showing live tissues; NOTE light green pistil in the bud center



Winter damaged peach buds contain dried and brown tissue
Winter damaged peach buds contain yellow, brown and discolored tissues


The fact that there are blooms on your tree is really good news, but that doesn’t necessarily mean that you’ll have fruit.  Now, even with blossoms on the trees, those other lesser known but critical factors come into play.  The first biggie is—How will weather impact pollinator (typically honeybee) activity?  Yes, I know that peaches are self-fertile or do not need another peach cultivar to cross-pollinate them; however, research indicates that more fruit and higher quality fruit is set on all cultivars when blooms are visited by bees.  A drawback of self-pollinated fruits always seems to be a lower number overall of fruits produced.   This lack of lower fruit numbers overall is directly traceable to insufficient insect (honeybee) visits to the flowers during bloom to accomplish that self-pollination!


Top peach bud anthers appear damaged; bottom bud is viable
Top peach bud stamens appear damaged; bottom bud has excellent pistil and stamen tissues


We love honeybees but they can be a little finicky on when they go a-pollinating!  Honeybees do not like cold, wet (rain is like dodging missiles) and breezy (wind speeds greater than 15mph) conditions.  This type of weather can cause honeybees to stop their foraging flights and just hang out at the hive.  In fact, the minimum temperature for honeybee flight is 54°F.  The optimum temperature for flight activity is 72-77°F, but honeybee foraging continues up to about 100°F before declining.  Pollinators working the “self-pollinating” flowers will help to ensure fruit production.


Peach bloom with pistil and ripe stamens
Peach bloom opening with emerging pistil and ripe stamens full of pollen


You are excited to see the beautiful pink petals of peach flowers and start dreaming of peach tarts or pies… But wait, did you check the flowers to see if the pistils and stamens are undamaged?  The most common assumption made is that if the petals look good, then everything is just peachy!  But that is simply not always the case and often the pistil must be pollenized with viable pollen, which in turn fertilizes the ovary, eventually developing into the peach.  The other critical part of pollination/fertilization equation is that stamens provide the necessary viable pollen to fertilize the pistil, so that it will develop into a peach.  One or the other or both of these critical flower parts can be affected during the winter.


Cut open peach bloom showing viable pistil and stamens
Cut open peach blossom showing viable light-green pistil in the center surrounded by developing stamens; lower bud has been winter damaged


If blooms make it through winter unscathed, is it time to get excited about peach cobbler… NO!  We still have to run the gauntlet of really warm Spring temperatures causing blooms to swell, expand and emerge appearing to explode overnight on the tree and… WHAMMO!  Out of nowhere comes a FROST, FREEZE or SNOW event to damage one or all of these flower parts!  The damage can be outright catastrophic, like freezing the cells of the tender tissues of the entire flower, causing them to burst, turn brown and die.  All the dreams involving peach crumble desserts just crumbled!


Expanded peach bud with apparent damage to the stamens
Expanded peach bud showing apparent damage to stamens and stigma 


But sometimes, the damage is really subtle and something as insidious as slightly damaging cells of the stigma, but not damaging at all any of the other parts of the flower.  The stigma is the sticky surface at the very tip of the pistil that receives the pollen grains and allows the incredible, miraculous process of fertilization to begin.  If the stigma is damaged or burned off by the frost or freezing temperatures, then no pollination nor fertilization can happen… so you just got shorted peaches for shortbread!


Peach bloom apears viable but carefully note the dried-up pistil
Cut peach bud shows petal tissues and stamens are viable; NOTE the brown, dried-up, winter damaged pistil in the flower center


Hopefully, you now have a better appreciation for the miracles and the woes involved with trying to grow fruit in NE Ohio.  The beauty is when these factors all fall perfectly into place, then you can grow and produce some pretty tasty fruit!  Even if we don’t talk about other potential impacts like thunderstorm winds, hailstorms, fungal brown rot, insect pests like Japanese beetles, crows sampling and those thieving squirrels!  Instead, we’ll spend our time dreaming of pans full of peach crisp, bottles of prize-winning preserves, peach cobbler or just summertime topped off with peach ice cream!


All lower peach buds were winter damaged by cold but note viable buds still up in the tops of the trees
Still hope for peaches!  NOTE All lower peach buds were winter damaged by cold but viable buds expanding in the tree tops