Apple care guide: when & how to prune, fertilize and spray

When: 2–8 weeks before the last spring frost.

• zones 3–5: about Mar 15 – Apr 26
• zones 6–7: about Feb 18 – Apr 1
• zones 8–10: about Dec 31 – Feb 11

Opens the canopy so sun reaches every apple and air dries the leaves. That's your first defense against scab, and it maintains strong, fruit-bearing wood.

1. Prune on a dry day in late winter, after the coldest weather.
2. Remove the 3 Ds (dead, damaged, diseased), then root suckers and water sprouts.
3. Remove branches that cross, rub, grow downward or grow back into the center.
4. Keep a central leader with 3–5 well-spaced scaffold branches at wide angles (45–60°). Remove narrow V-shaped crotches.
5. Thin crowded areas so you could toss a hat through the canopy, but leave short, stubby fruiting spurs alone.
6. Remove no more than 25% of the canopy in one year.
7. Cut just outside the branch collar, without leaving stubs or making flush cuts.

Tools: Bypass pruners, Loppers, Pruning saw, Orchard ladder

When: 5–8 weeks after the last spring frost.

• zones 3–5: about Jun 14 – Jul 5
• zones 6–7: about May 20 – Jun 10
• zones 8–10: about Apr 1–22

Trees set far more fruit than they can size up. Thinning gives bigger, better-tasting fruit, prevents broken branches and stops the tree alternating between heavy and empty years.

1. Wait until after the natural 'June drop', when fruit is about marble to walnut size.
2. Twist or snip off fruit so the survivors are spaced 6–8 in (15–20 cm) apart along the branch.
3. Remove the smallest, damaged or misshapen fruit first.
4. It feels wasteful, but you'll harvest about the same weight of much better fruit.

When: 12–16 weeks after the last spring frost.

• zones 3–5: about Aug 2–30
• zones 6–7: about Jul 8 – Aug 5
• zones 8–10: about May 20 – Jun 17

Water sprouts (vertical shoots) shade the fruit and waste energy. Pruning them in summer causes less regrowth than pruning in winter.

1. Snap or cut off upright, whip-like shoots growing straight up from main branches.
2. Remove root suckers at the base.
3. Keep it light. Summer pruning should remove less than 10% of the leaves.

When: from 3 weeks before to 1 week after the last spring frost.

• zones 3–5: about Apr 19 – May 17
• zones 6–7: about Mar 25 – Apr 22
• zones 8–10: about Feb 4 – Mar 4

Feeding before bud break supports flowering and fruit set. Mature trees growing 8–12 in (20–30 cm) a year may need nothing.

1. Spread fertilizer evenly in a band from 1 ft (30 cm) off the trunk to beyond the drip line.
2. Rough guide: 1 cup of 10-10-10 per year of tree age, up to a max of 10 cups (or the equivalent organic product).
3. Skip it if the tree grew more than 12 in (30 cm) last year. Excess nitrogen invites fire blight.

What to use: 🌿 Organic tree & shrub food (e.g. Espoma Tree-tone 6-3-2) · 🌿 Finished compost or composted manure · Fruit tree spikes or 10-10-10 granular

When: 2–6 weeks before the last spring frost.

• zones 3–5: about Mar 29 – Apr 26
• zones 6–7: about Mar 4 – Apr 1
• zones 8–10: about Jan 14 – Feb 11

Smothers overwintering aphid eggs, mites and scale before they hatch. It's the lowest-toxicity insect control you can do all year.

1. Pick a calm, dry day between 40°F and 70°F (4–21°C) with no freeze forecast for 24 hours.
2. Mix the oil at the label's dormant rate.
3. Coat every branch, crotch and bark crevice until it drips.
4. Spray before buds open. Oil on tender green tissue can burn it.

What to use: 🌿 Horticultural / dormant oil (e.g. Bonide All Seasons Oil)

Caution: Don't use within 2 weeks of a sulfur spray. Don't spray blue spruce or other blue conifers; oil strips their color.

When: 2–6 weeks before the last spring frost.

• zones 3–5: about Mar 29 – Apr 26
• zones 6–7: about Mar 4 – Apr 1
• zones 8–10: about Jan 14 – Feb 11

Kills overwintering spores of fire blight and scab on bark and bud scales before they can infect new growth.

1. Spray on a dry day above 40°F/4°C, just before buds swell.
2. Cover all bark and buds thoroughly.
3. Rinse your sprayer well afterward. Copper corrodes metal parts.

What to use: 🌿 Copper fungicide (e.g. Bonide Captain Jack's Liquid Copper) · 🌿 Lime sulfur (e.g. Lime-Sulfur Spray)

When: from 2 weeks before the last spring frost until the last spring frost, then every 2 weeks (5 times a season).

• zones 3–5: about Apr 26 – May 10
• zones 6–7: about Apr 1–15
• zones 8–10: about Feb 11–25

Scab infects leaves and young fruit during wet spring weather from green tip until a few weeks after petal fall.

1. Start at green tip (when ¼ in / 6 mm of green leaf shows) and repeat every 7–14 days, before forecast rain.
2. Cover all leaves and young fruit.
3. Never spray insecticides while trees are in bloom. Bees are pollinating your crop.
4. Skip this if you grow scab-resistant varieties (e.g. Liberty, Enterprise, Freedom).

What to use: 🌿 Wettable sulfur (e.g. Bonide Sulfur Plant Fungicide) · 🌿 Bacillus-based biofungicide (e.g. Serenade or Cease) · Captan (fruit tree fungicide) · Myclobutanil (e.g. Spectracide Immunox)

Caution: Don't combine sulfur and oil sprays within 2 weeks of each other.

When: 4–6 weeks after the last spring frost, then every 2 weeks (4 times a season).

• zones 3–5: about Jun 7–21
• zones 6–7: about May 13–27
• zones 8–10: about Mar 25 – Apr 8

Most 'wormy apples' come from codling moth larvae entering young fruit in the weeks after petal fall.

1. Start once all petals have fallen.
2. Spray kaolin clay to coat fruit in a white film (renew after rain), or spinosad at dusk.
3. Or slip a nylon footie or paper bag over individual thinned fruit.

What to use: 🌿 Kaolin clay (e.g. Surround WP) · 🌿 Spinosad (e.g. Captain Jack's Deadbug Brew) · Acetamiprid (e.g. Ortho Flower, Fruit & Vegetable Insect Killer)

When: 3–8 weeks before the last spring frost.

• zones 3–5: about Mar 15 – Apr 19
• zones 6–7: about Feb 18 – Mar 25
• zones 8–10: about Dec 31 – Feb 4

This plant prefers a pH of 6.0–7.0. A soil test tells you whether you need lime, sulfur or extra nutrients, so you aren't guessing.

1. Take 6–8 small samples from the root zone, 4–6 in (10–15 cm) deep, using a clean trowel.
2. Mix them in a clean bucket, let the soil air-dry, and send about 2 cups to your local extension office or a soil lab. A home kit works but is less accurate.
3. Follow the lime or sulfur amounts in the report. Change pH slowly: no more than 1 unit a year.

Tools: Clean trowel, Plastic bucket, Soil test kit or lab mailer

When: 2–6 weeks after the first fall frost.

• zones 3–5: about Oct 15 – Nov 12
• zones 6–7: about Nov 8 – Dec 6
• zones 8–10: about Dec 15 – Jan 12

Voles and rabbits girdle young fruit tree trunks under snow, and winter sun can split bark (sunscald).

1. Wrap the lower 18–24 in (45–60 cm) of young trunks with a plastic spiral guard or hardware cloth.
2. Pull mulch back from the trunk so voles have nowhere to hide.
3. Optionally paint the trunk with diluted white latex paint (50:50 with water) to prevent sunscald.

When: from the first fall frost to 4 weeks after.

• zones 3–5: about Oct 1–29
• zones 6–7: about Oct 25 – Nov 22
• zones 8–10: about Dec 1–29

Spores of apple scab overwinter on fallen leaves and splash back up in spring. Removing them is the single best way to prevent next year's outbreak.

1. Rake up and remove fallen leaves and dropped fruit from under the plant.
2. Bag diseased material or put it in the trash. Don't compost it unless your pile gets hot (140°F/60°C+).
3. Cut out any dead or obviously diseased twigs you can see.

Tools: Rake, Bypass pruners