Kumquat Tree

The most cold-hardy of the citrus family, this compact tree produces small oval fruits eaten whole, skin and all. Kumquats have a unique flavor profile with sweet edible rind and tart interior flesh. Their small size makes them excellent container plants for patios and indoor growing in bright sunlight. They bloom later than other citrus, which helps them avoid late spring frost damage on flowers.

Kumquat trees are typically propagated by grafting onto trifoliate orange or Flying Dragon rootstock, which provides cold hardiness and controls tree size. Purchase grafted nursery stock for best results and earliest fruiting. Kumquats can also be grown from semi-hardwood cuttings taken in summer, treated with rooting hormone and placed under intermittent mist. Seed-grown kumquats are more true to type than most citrus but still take 5 to 7 years to fruit compared to 2 to 3 years for grafted trees.

The Season Plate

Your Kumquat Tree Year

Composed for Zone 7 · typical seasons · frost passes Apr 2, returns Nov 1

Sow Kumquat Tree Mar – May, pick Jan – Mar, Nov – Dec. Set your climate below and every date on this plate re-times itself.

Sowing window

Mar – May

re-timed to your frost dates

Plant out

after Apr 2

once frost risk has passed

First picking

around Mar 14

≈ 730 days from sowing · 2 to per plant

Composed for —ColdTemperateMildWarmUse my locationUsed once to set your season · only the zone is kept

Week-by-week Kumquat Tree reminders watering, feeding and pruning, timed to your dates

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Frost alerts for your garden a warning before a cold night costs you the crop

In the app

Succession sowing dates so the picking never gaps mid-season

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Get my Kumquat Tree datesSaved to your free garden plan · no card needed

Kumquat trees are the most cold-tolerant true citrus, surviving temperatures down to about 18 degrees Fahrenheit when fully dormant. Plant in full sun in well-drained soil with a pH of 6.0 to 7.0. Their compact size, typically reaching 8 to 12 feet tall, makes them ideal for small gardens, patios, and container growing. Space in-ground trees 8 to 10 feet apart, or use 15 to 20 gallon containers for patio growing.

Water kumquats regularly during the growing season, keeping soil evenly moist but not waterlogged. Container-grown trees dry out faster and may need watering every 2 to 3 days during summer heat. Feed with a citrus-specific fertilizer every 6 to 8 weeks from spring through early fall. Kumquats are lighter feeders than most citrus, so avoid over-fertilizing which can reduce fruit quality and promote excessive vegetative growth.

Kumquats bloom later than other citrus, typically in midsummer, which helps them avoid late spring frost damage. Fruit takes several months to ripen and is usually ready for harvest from November through March. The trees require very little pruning beyond removing dead or crossing branches and maintaining a pleasing shape. In cold-winter areas, container kumquats can be overwintered in a bright, cool room at 50 to 60 degrees Fahrenheit with reduced watering.

Kumquats pair well with other compact plants that share their preference for well-drained soil and full sun. Interplant with lavender, rosemary, and thyme to attract pollinators and create an aromatic herb garden. Marigolds planted nearby repel whiteflies and nematodes. In container groupings, surround kumquats with basil, dwarf peppers, and trailing nasturtiums for an edible patio display. Avoid planting in lawn areas where grass competition reduces tree vigor.

The Society Table

Basil belongs beside it. Walnut Tree doesn't.

Old growers' knowledge, checked against Kumquat Tree's real companion table below — test any plant you're growing.

Grows well in the company of · 3

BasilLavenderMarigold

Keep apart · 1

Walnut Tree

Plant Kumquat Tree with good neighboursThe planner flags conflicts before they're in the ground

Related growing guides

Herbs

Basil

A good companion for Kumquat Tree

Herbs

Lavender

A good companion for Kumquat Tree

Flowers

Marigold

A good companion for Kumquat Tree

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Apple Tree

View growing guide

Kumquats grow well in a range of well-drained soils from sandy loam to clay loam with a pH of 5.5 to 7.0. They are more tolerant of less-than-ideal soil conditions than most citrus. Apply a balanced citrus fertilizer three to four times during the growing season at moderate rates. Supplement with chelated iron if yellowing between leaf veins appears. For container trees, use a premium citrus potting mix and feed with liquid citrus fertilizer every 4 weeks during active growth.

Ideal Temperature

Hardiness Zone Compatibility

Kumquats are unique among citrus because they are eaten whole, skin and all. Harvest when fruit is fully colored deep orange and slightly soft to the touch. The sweet rind contrasts beautifully with the tart interior flesh. Taste-test a fruit to check ripeness, as color can be deceptive. Fruit can hang on the tree for several weeks after ripening without deteriorating, allowing for an extended harvest period throughout winter.

Storage & Preservation

Fresh kumquats keep at room temperature for several days and in the refrigerator for 2 to 3 weeks. Store in a plastic bag to prevent drying. Kumquats are exceptional for preserving whole in sugar syrup, making marmalade, or candying. They can be frozen whole for use in smoothies and cooking. Kumquat preserves and chutneys make excellent condiments, and the fruit can be sliced and dried for snacking or adding to tea.

Aphids

Pest

Clusters of small green, black, or brown insects on new growth and leaf undersides. Leaves curl and become sticky with honeydew, often developing sooty mold.

Prevention Encourage ladybugs, lacewings, and other natural predators. Avoid excessive nitrogen fertilization that produces soft, aphid-attracting growth.

Fix: Spray with a strong jet of water to dislodge aphids. Apply insecticidal soap or neem oil for persistent infestations. Horticultural oil smothers eggs and crawlers.

Citrus Melanose

Disease

Raised, rough brown spots on fruit, leaves, and twigs giving a sandpaper-like texture. Primarily cosmetic but reduces fruit appearance.

Prevention Prune dead twigs and branches where the fungus overwinters. Maintain good air circulation through the canopy.

Fix: Apply copper fungicide sprays in spring as new growth emerges. Remove and destroy heavily infected deadwood to reduce spore sources.

Spider Mites

Pest

Fine stippling on leaves that appear dusty or bronze. Tiny webbing visible between leaves and stems in severe infestations. Leaves may drop prematurely.

Prevention Maintain adequate humidity around container trees. Avoid dusty conditions and broad-spectrum pesticides that kill mite predators.

Fix: Spray leaves thoroughly with water to reduce populations. Apply miticide or horticultural oil, covering both upper and lower leaf surfaces. Repeat every 5 to 7 days.

Troubleshooting Common Problems

Fruit drop before maturity often results from water stress, either too much or too little, during fruit development. Container-grown kumquats are prone to root binding and nutrient deficiency if not repotted every 2 to 3 years. Indoor trees may drop leaves from insufficient light or low humidity during winter. Thorn production is common, especially on vigorous young growth, but thorns diminish as trees mature. Irregular watering causes fruit splitting on nearly ripe fruit.

Growing Tips

1. Choose a grafted nursery tree over seed-grown stock for faster fruiting and true-to-type variety characteristics.
2. Plant in well-draining, slightly acidic soil with a pH between 5.5 and 6.5 for optimal nutrient uptake.
3. Position the tree in a location receiving at least 6 to 8 hours of direct sunlight per day for the best fruit production.
4. Water deeply but infrequently, allowing the top 5 cm of soil to dry between waterings to prevent root rot.
5. Apply a slow-release citrus fertilizer three times per year: in early spring, early summer, and early autumn.
6. Protect young trees from frost with frost cloth or by bringing container plants indoors when temperatures drop below -4°C (25°F).
7. Prune after the harvest season to maintain shape and remove any dead, diseased, or inward-growing branches.
8. Watch for common pests such as scale insects, aphids, and citrus leaf miners, and treat with horticultural oil or neem oil.
9. Mulch around the base of the tree with organic material, keeping mulch 10 cm away from the trunk to prevent collar rot.
10. For container growing, use a pot at least 50 cm in diameter with drainage holes and repot every 2 to 3 years to refresh the soil.