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

When: from the last spring frost to 4 weeks after.

• zones 6–7: about Apr 15 – May 13
• zones 8–10: about Feb 25 – Mar 25

Mandarins fruit all over the canopy and need little pruning. Pruning in spring, after harvest and once frost risk has passed, keeps them tidy without losing much crop.

1. Remove any shoots growing from below the graft union (the bump near the base). They're thorny rootstock suckers.
2. Cut out dead, damaged and crossing twigs, plus very vigorous upright water sprouts.
3. Lightly thin the center if it's dense, so light and air can reach inside.
4. Lift the skirt so lower branches are about 1–2 ft (30–60 cm) off the ground, which keeps fruit clean and reduces disease. Leave some low branches in cold areas: they shield the trunk.
5. Remove no more than 20% of the canopy at once.

Tools: Bypass pruners, Gloves

When: 10–14 weeks after the last spring frost.

• zones 6–7: about Jun 24 – Jul 22
• zones 8–10: about May 6 – Jun 3

Mandarins tend to overbear one year and rest the next. Thinning a heavy crop gives bigger, sweeter fruit and a more even crop next year.

1. After the early-summer natural fruit drop, look at how heavily the tree has set.
2. In heavy years, remove small, damaged and clustered fruit so the rest are spaced about 4–6 in (10–15 cm) apart.
3. Skip this in light years.

When: 1–4 weeks before the last spring frost.

• zones 6–7: about Mar 18 – Apr 8
• zones 8–10: about Jan 28 – Feb 18

Mandarins need nitrogen plus micronutrients (iron, zinc, manganese, magnesium) to flower and hold fruit. Feed 3 times a year in the ground, or monthly in containers.

1. Spread citrus fertilizer evenly from about 1 ft (30 cm) off the trunk to just beyond the drip line, then water it in.
2. Containers: use slow-release or liquid citrus food monthly from spring to early fall.

What to use: 🌿 Organic citrus food (e.g. Espoma Citrus-tone 5-2-6) · Citrus & avocado fertilizer with micronutrients (e.g. Jobe's or Vigoro)

When: 8–10 weeks after the last spring frost, then every 8 weeks (2 times a season).

• zones 6–7: about Jun 10–24
• zones 8–10: about Apr 22 – May 6

Keeps leaves dark green and fruit sizing up through summer.

1. Repeat the citrus feeding and water it in well. Stop feeding by late summer so new growth hardens before winter.

What to use: 🌿 Organic citrus food (e.g. Espoma Citrus-tone 5-2-6) · Citrus & avocado fertilizer with micronutrients (e.g. Jobe's or Vigoro) · Chelated iron (e.g. Ironite or liquid chelated iron), for yellowing between veins

When: 6–8 weeks after the last spring frost, then every 8 weeks (3 times a season).

• zones 6–7: about May 27 – Jun 10
• zones 8–10: about Apr 8–22

Sap-sucking pests build up quickly on citrus, especially indoors and when ants are tending them.

1. Look under leaves and along twigs for bumps, cottony masses, clusters of aphids or sticky honeydew.
2. If you find them, spray horticultural oil (summer rate) or insecticidal soap, covering leaf undersides. Repeat in 2 weeks.
3. Don't spray oil above 85°F (29°C) or on drought-stressed trees.

What to use: 🌿 Horticultural / dormant oil (e.g. Bonide All Seasons Oil) · 🌿 Insecticidal soap (e.g. Safer Brand) · 🌿 Neem oil (e.g. Garden Safe Neem Oil Extract)

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

• zones 6–7: about Apr 29 – May 27
• zones 8–10: about Mar 11 – Apr 8

Mulch keeps roots cool and moist, suppresses weeds and slowly feeds the soil. Applying it after the soil warms lets roots wake up first.

1. Spread 2–3 in (5–7 cm) of mulch over the root zone.
2. Keep mulch 2–3 in (5–7 cm) away from stems and trunks. Mulch piled against bark invites rot and rodents.
3. Don't go deeper than 3 in (7 cm) in total. Too much mulch suffocates roots.

What to use: 🌿 Shredded hardwood or pine bark mulch

When: from 2 weeks before to 1 week after the first fall frost.

• zones 6–7: about Oct 11 – Nov 1
• zones 8–10: about Nov 17 – Dec 8

Satsumas are the hardiest mandarin (about 20°F / −7°C when established), but young trees and most tangerines are damaged below about 26–28°F (−3 to −2°C).

1. Containers: move into a garage or bright room before nights drop below 32°F (0°C).
2. In-ground trees: water the soil well the day before a freeze, then cover to the ground with frost cloth at dusk. String warm Christmas lights (not LED) under the cover on very cold nights.
3. Mound soil or mulch around the lower trunk of young trees in winter to protect the graft union.

When: from 2 weeks before to 8 weeks after the first fall frost.

• zones 6–7: about Oct 11 – Dec 20
• zones 8–10: about Nov 17 – Jan 26

Most mandarins ripen from late fall into winter. Unlike many fruits, they don't ripen further after picking.

1. Taste-test one fruit. Color isn't a reliable guide: satsumas are often sweet while still partly green.
2. Clip fruit with a short stem using pruners rather than pulling, which tears the peel.
3. Satsumas and clementines turn puffy if left too long, so pick within a few weeks. Later varieties (e.g. Tango, Murcott) hold on the tree for weeks.
4. Pick ripe fruit before a hard freeze below about 26°F (−3°C).

Tools: Bypass pruners, Picking bag