Orchard Frost - Assessing Fruit Bud Survival

Following a freeze event in your orchard, focus on bud survival by using a technique Jim Schupp adapted from strategies to adjust crop load at thinning time.
Orchard Frost - Assessing Fruit Bud Survival - Articles

Updated: April 14, 2016

Orchard Frost - Assessing Fruit Bud Survival

Peach trees are in full bloom in many orchards, while apple trees are at the tight cluster stage.

Peach Bud Survival

Compare the number of live buds to the number a fruiting lateral should carry based on the target yield per acre

  1. To get a good estimate, examine about 150 to 200 flower buds per variety per block.
  2. Collect one strong fruiting lateral (pencil thick and 16 to 22 inches long) from each of two sides of 5 representative trees per block.
  3. Bring the fruiting laterals into a heated building, place them in buckets of water, and allow them to warm up overnight.
  4. Slice each bud open lengthwise with an exacto knife, single edged razor blade, or scalpel. Examine the pistil in the center of each flower, and count the number that are healthy.
  5. Compare this number per fruiting lateral to your desired crop load. If, for example, you have 12 live flower buds on a fruiting lateral that should carry 3 peaches at harvest, then you have four times as many live flower buds as are required for a full crop.


Peach shoot following evaluation for bud survival.

Apple Bud Survival

Compare the number of live buds to the target number for the branch diameter, using an Equilifruit disk.

  1. Collect one 3/8 to 1/2 inch diameter branch from each of two sides of 5 representative trees per block. Preferably, there should be no heading cuts on these branches, so this technique works best with tall spindle-trained trees.
  2. Bring the branches into a heated building, place them in buckets of water, and allow them to warm up overnight.
  3. Slice each bud open lengthwise with an exacto knife, single edged razor blade or scalpel. Dissect the buds and count the number of king and side bloom with live ovules and styles.
  4. Measure the diameter of the base of the branch with an Equilifruit disk to determine the number of fruit needed on that limb to set a full crop. Compare the number of live buds to this number. If, for example, you have 20 live flower buds on a branch that should carry 4 apples at harvest, then you have five times as many live flower buds as are required to have a full crop.


Apple shoot to be evaluated for bud survival. Each flower bud will be dissected longitudinally.

Photos by E. Winzeler

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