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Apple buds opening before a hard freeze

A low of 25°F is forecast while your tree's buds are opening. Opening buds can start to be damaged at about 18–23°F, and buds can be a few degrees colder than the air on clear, calm nights. A tree needs only a small share of its buds to set a good crop, so a big tree you can't cover will often be fine.

When we suggest this

  • ForecastA night at or below about 25°F is forecast for tonight or the next 2 nights.
  • Your noteYour note: stage is buds opening (silver or green tip).

What would stop us suggesting it

  • The morning after the forecast night passes (or when a fresh forecast no longer shows it).
  • When you mark it Done or Doesn't apply. "Doesn't fit my setup" stops it for that plant this season.

What to do

  1. For a small tree, drape a frost cloth, old sheet, or burlap over it in the late afternoon so it reaches the ground all around.
  2. Keep plastic off the buds and branches.
  3. If the soil under the tree is dry, water it during the day. Moist soil holds more heat.
  4. Take the cover off late the next morning, once it's above freezing.

What we can't know

  • How far the buds have opened. Buds with half an inch of green showing are more tender than buds just showing silver.
  • How cold it gets at your tree. Low spots can be several degrees colder than the forecast.

WSU research on 'Red Delicious' found about 10% bud kill after 30 minutes at 15°F (silver tip), 18°F (green tip), and 23°F (half-inch green), and 90% kill at 2–15°F. We use 25°F, about 2°F above the most tender of these, because buds cool below air temperature on clear, calm nights (up to about 5°F) and yards differ from the forecast point. Cool weather before the freeze makes buds hardier. Iowa State notes there is often little a backyard grower can do once buds have swelled.

Where this advice applies

All US regions.

Any US garden where a hard freeze can follow bud break.

Low spots and the bottoms of slopes collect cold air and run colder than the forecast.

Exceptions

  • Trees still dormant or already past this stage (answer the stage check-in).
  • Trees you've marked finished for the season.

Related guide sections

Sources

  1. Washington State University Extension. Critical Temperatures for Blossom Buds: Apples (EB0913). Accessed September 25, 2026
  2. Penn State Extension. Orchard Frost - Critical Temperatures for Various Fruits. Accessed September 25, 2026
  3. Utah State University Extension. Critical Temperatures for Frost Damage on Fruit Trees (IPM-012-11). Accessed September 25, 2026
  4. Texas A&M AgriLife Extension. Protecting Landscapes and Horticultural Crops from Frosts and Freezes (EHT-048). Accessed September 25, 2026
  5. Utah State University Extension (IPM Pest Advisories). Frost Protection. Accessed September 25, 2026
  6. Iowa State University Extension and Outreach. Spring 2026: A weather rollercoaster for apple flower buds. Accessed September 25, 2026

Reviewed

Sources checked Sept 2026 · awaiting expert review

Gardenplanner research (AI-assisted), pending extension-qualified review

Rule id and version: apple.bud-freeze@1