Kumquat Fruit: How to Grow, Protect and Use Kumquats

By the Garden Voila editorial team · Updated October 28, 2026 · How we verify

Kumquats are the citrus you eat whole. The peel is sweet, the pulp is tart, and the combination is surprisingly addictive. They are also among the hardiest citrus trees and small enough to grow in a pot, which makes them a good choice for gardeners in cooler climates. This guide covers the main types, how cold they can really take, how to plant, water, feed and protect a kumquat tree, how to grow one in a container, when to harvest and how to turn the fruit into marmalade, candied fruit and more.

What is a kumquat?

Kumquats are small, orange citrus fruit about the size of a large olive or small plum. Unlike most citrus, you eat the skin along with the flesh. The rind carries the sweetness and the juicy pulp carries the sour punch, so rolling the fruit gently between your fingers before eating blends the two flavors. The sweetest varieties have edible skin and can be eaten fresh, according to the Almanac Garden Planner kumquat guide, and the fruit is also used for marmalade or candied whole. Kumquats are technically in the same family as other citrus but are classed separately (Citrus japonica or Fortunella in older references), and they can cross with other citrus nearby.

Popular types

The University of Georgia’s citrus bulletin for southern and coastal Georgia, UGA Extension bulletin B804, lists Nagami, Marumi and Meiwa as the kumquat selections for the region, and mentions the limequats Lakeland, Eustis and Tavares as related cold-tolerant hybrids.

Kumquat tree quick facts

How cold can a kumquat take?

Kumquats are among the hardiest citrus, but they are not hardy in the way a peach or apple is. UGA’s bulletin says kumquats tolerate roughly 15 to 17°F, whereas calamondins and limequats tolerate about the low 20s °F, and mandarins show wood damage in the low 20s. The Almanac guide is more cautious, saying that the popular Nagami and Meiwa varieties survive only to about 20°F. Both agree they are the smallest and most cold-hardy edible citrus. A few practical notes:

• Duration matters as much as temperature. A brief dip to 20°F is much less damaging than several hours below freezing.
• Young trees and trees still growing in autumn are far less hardy than mature, dormant trees.
• Wet, windy nights are harder on trees than calm, clear ones, and cold air pools in low spots.
• Fruit freezes at about 26 to 28°F, so harvest before a freeze when you can.

Mississippi State University Extension’s fruit and nut review of citrus reminds Gulf Coast growers that citrus is tropical or subtropical in origin, so winter protection is required, and that severe winters have killed many outdoor trees back to the graft union. If your area regularly falls below the mid-teens, grow your kumquat in a pot.

How to grow a kumquat

1. Choose the spot. Full sun and shelter from cold wind. A south-facing wall helps. Confirm your zone with the growing zone finder.
2. Plant in late winter or early spring, after the danger of hard frost has passed. Almanac advises setting the root ball a little above the soil line (about an inch), and UGA recommends avoiding fall and winter planting.
3. Space generously. UGA suggests 6 to 10 feet for kumquats; Almanac says at least 10 feet apart. Use the plant spacing calculator.
4. Keep mulch off the trunk, and spread 2 to 4 inches around the tree. See the mulch calculator.
5. Water deeply but let the top inch or two dry between waterings. Almanac suggests deep watering about every 10 days during dry weather. Citrus hates soggy roots. See the garden watering calculator.
6. Feed regularly. Almanac suggests spreading rich compost over the root zone twice a year, while UGA says to use a balanced citrus fertilizer and avoid feeding from August to mid-February. Follow the label rates.
7. Prune lightly to shape the tree and remove dead or injured wood after harvest. Kumquats need very little pruning.

Growing kumquats in containers

In zones colder than 8, grow a kumquat in a large pot with drainage holes and move it indoors or to a bright, protected spot before the first freeze. Almanac advises using the largest planter practical, since the plant must be moved in winter. Use a gritty, well-draining potting mix, and a pot that suits the tree’s size, with a minimum of about 15 gallons for a mature tree. In summer, keep the pot in full sun and water as soon as the top couple of inches dry. In winter, give a cool, bright spot, around 45 to 60°F, and water sparingly. Check container plants for aphids and other pests before bringing them inside, and acclimate them gradually to indoor light to avoid leaf drop. A kumquat can live happily as an indoor-outdoor plant if it has a warm, sunny spot for winter.

Protecting a kumquat from frost

• Water the soil before a cold night; moist soil holds more heat than dry soil.
• Cover the tree with frost cloth or blankets that reach the ground. UGA notes that covers work best when they touch the soil, and that one or two electric bulbs under the cover add protection on extreme nights.
• Bank young trees with soil about 15 inches high before the first freeze, as UGA advises for trees up to four years old.
• Move containers into an unheated garage, porch or greenhouse on cold nights.
• Harvest ripe fruit ahead of a hard freeze, since unharvested fruit raises freeze damage risk.

Check frost dates by ZIP code to know when your first cold nights typically arrive.

Pests and problems

Kumquats have few pest problems. Almanac lists aphids, slugs and snails as the main ones, and advises watching for citrus pests and diseases where commercial citrus is grown nearby.

• Aphids: curled new growth. See how to get rid of aphids.
• Scale and sooty mold: sticky leaves and black mold. See scale insects.
• Citrus leaf miner: winding trails in new leaves, mostly cosmetic. See citrus leaf miner.
• Slugs and snails: see garden snails and slugs.
• Yellow leaves: often cold stress, overwatering or a nutrient shortage. Check drainage first.

Harvest

Kumquats bloom and set fruit over several weeks, so they ripen unevenly. Ripe fruit turns bright orange, and overripe fruit drops from the plant. The fruit ripens in winter, and you can leave it on the tree for a few weeks, picking as you need it. Cut it from the stem with scissors. Refrigerate harvested fruit until you preserve it, and store it in a perforated bag for a couple of weeks. Taste a fruit to judge ripeness, because the color alone is not always a perfect guide.

Using kumquats

• Fresh: pop whole fruit in your mouth, or slice and remove seeds for salads.
• Marmalade: slice thinly, remove seeds, simmer with sugar and water until the peel is tender and the mixture sets.
• Candied: simmer whole or halved fruit in sugar syrup, then dry for a long-keeping treat.
• Cocktails and drinks: muddle slices into drinks or infuse spirits.
• Chutney and sauces: a classic pairing with duck and pork.

Simple kumquat recipes

Quick candied kumquats

1. Wash 1 pound of kumquats, slice them into rounds and pick out the seeds.
2. Blanch the slices in boiling water for 1 minute, then drain, to soften the bitterness.
3. Simmer 1 cup of sugar and 1 cup of water to a syrup, add the slices and cook gently for 20 to 30 minutes until translucent.
4. Lift the slices out, dry them on a rack and store in an airtight container, or keep them in their syrup in the refrigerator.

Kumquat marmalade

Slice 1 pound of fruit thinly, discard the seeds (tie them in a muslin bag and cook with the fruit, since they hold pectin), cover with 3 cups of water and simmer until the peel is soft. Add about 2 cups of sugar and the juice of a lemon and boil until the mixture sets on a cold plate. Pour into clean jars. If you plan to keep it at room temperature, follow a tested canning recipe and process it correctly. See water bath canning for beginners.

Buying a kumquat tree

Most kumquats are grafted onto a citrus rootstock for vigor and pest resistance, according to the Almanac guide, and a purchased tree of a good cultivar typically bears two to three years after planting. Buy only from a reputable nursery that supplies certified, disease-free citrus. Avoid trees with yellow, spotted leaves, crowded roots circling the pot or a swollen, damaged graft union. In colder areas, buy a tree in a container so you can move it indoors. A nursery in your region will also be able to tell you which variety performs best locally, since Nagami, Meiwa and Marumi differ in flavor, size and cold tolerance.

A kumquat year at a glance

• Winter: harvest ripe fruit, protect from hard freezes and keep container trees in a cool, bright place.
• Late winter to early spring: remove any frost-damaged wood after the last frost, plant new trees and apply the first feeding.
• Spring: flowers appear in late spring to summer. Keep the soil evenly moist, and welcome pollinators.
• Summer: water deeply, shade young trees from the harshest afternoon sun, and check for pests.
• Fall: stop feeding by August, and prepare covers and heaters before the first freeze.

Troubleshooting

• Leaves dropping after moving indoors: sudden changes in light and humidity. Acclimate gradually.
• No flowers or fruit: too little sun, a tree that is still young or fed too much nitrogen.
• Fruit dropping: irregular watering, cold stress or overripe fruit.
• Sticky leaves: aphids or scale. Wash them off and treat early.
• Browned leaf edges: salt build-up or cold damage. Flush containers with water.
• Sprouts from below the graft: rootstock suckers. Remove them promptly, because they will not produce kumquats.

Why kumquats suit small gardens

A kumquat packs a lot into a small space. A single dwarf tree in a large pot can supply enough fruit for marmalade, snacking and garnishes, it looks good year-round with glossy evergreen leaves and fragrant white blossoms, and it is forgiving of the occasional missed watering once established. Because the tree is self-fertile and small, it is a practical first citrus for beginners, apartment balconies and cool-climate gardeners who want to try growing their own citrus without committing to a large orchard tree. Give it sun, good drainage and protection from the worst of the cold, and it will repay you with bright orange fruit in the dullest part of the year.

For related citrus see our guides to Meyer lemon in a pot, mandarin trees and lime trees, or browse the fruit tree growing guide.

Frequently asked questions

Reviewed October 2026. Hardiness and ripening vary by region.