Members of the Citrus family (Rutaceae) and Citrus genus, Kumquats are more cold
hardy than most cultivated citrus and have smaller fruit. The fruit rind is lacking citric acid,
which makes it sweet and edible, but provides less protection against insects.
Productive up to 50 years in a good location with proper care.
Leaf retention: Evergreen.
Growth rate: Slow.
8-25' high and as wide.
White, five petals, sweetly fragrant, borne singly or in a cluster of three or four.
Mid spring into fall, or throughout the year in regions without freezes.
All Kumquat cultivars self-pollinate.
Years before fruiting:
3 years after grafting.
Oval or round, golden yellow to reddish orange, 1" to 1.5" diameter, sweet edible rind,
tart to sweet flesh, entire fruit, except seeds are eaten. The seeds are a source of
Months for fruit to ripen:
6, depending on cultivar and micro-climate. The fruit are ripe when fully orange with
no trace of green. They do not ripen further after harvest.
Storage after harvest: At room temperature up
to 3 days, or refrigerate up to 2 weeks.
Glossy green, ovate. Citrus leaves have a tendency to turn pale-green or yellow in cold
weather. When temperatures warm back up in the spring, the leaves will green up.
Few or no thorns. Densely branched. The bark is prone to sunscald if not shaded by leaves
or covered by tree trunk paint, especially in higher temperatures.
Usually grafted on Trifoliate Orange (Citrus trifoliata) rootstock because its own roots
do not allow it to flourish.
Cultivars of Note:
'Meiwa' - nearly round shape, sweet thick rind
and pulp, sweetest tasting, 1.5" diameter.
'Nagami' - oval shape with sweet rind and tart
pulp, unique sweet-sour flavor, eaten whole, about 1" diameter. This cultivar is more
vigorous and hardy than others and grows faster. 'Nordmann Seedless' is a variation.
'Marumi' - round shape, sweet rind and pulp,
intermediate sweetness between Nagami and Meiwa, 1" diameter, flesh can be dry.
'Fukushu' / 'Changshou' - a hybrid, possibly
kumquat-mandarin, less cold hardy, oval with depressed apex, 1-1.5" long, sweet rind
and tart pulp, thornless, spreading dwarf tree with larger leaves, 6-10' tall.
Wildlife: Attracts bees, insects, birds, and is a
food plant for the Giant Swallowtail butterfly caterpillar – see Pests, below.
Mammals may strip the bark off of young shrubs, consume fallen fruit, or climb the shrub to
eat the fruit.
Toxic / Danger:
Cultivation and Uses
USDA hardiness zones:
Chill hours: None.
Heat tolerant: Less than other citrus members.
Drought tolerant: Yes.
In very hot climates, afternoon shade is necessary to reduce heat and water stress.
Avoid reflected heat.
Place the shrub in a sunny location with afternoon shade. Do not position it next to a
frequently watered location, such as grass. Make sure there is enough space for the shrub to
grow to its full width and height.
The best time to plant is after the danger of frost is past, in late winter or early spring.
Plant the shrub so that the root crown is at least one inch above ground level. The top
roots must extend out from the trunk, just above, and uncovered by, soil.
Kumquat can be grown in large containers. Indoors, in cold climates, the shrub should be placed
near a large, south-facing window.
Soil: Well drained, tolerate of soil types, pH 5.6-7.5
(acidic to neutral) for best results.
In desert soil, never use a chemical fertilizer to avoid salt buildup. Apply an organic
fertilizer, starting three months after planting, every month from mid-February to late
September. Apply plant micronutrients in irrigation water three times a year in February, May,
and August. Do not fertilize after September to keep the plant from producing new growth that
will be harmed by early frost.
Kumquat shrubs are small and grow slowly, so they need less fertilizer than most citrus
trees. These shrubs are prone to zinc deficiency, signaled by smaller leaves, reduced shoot
length and possibly yellow blotches between green leaf veins, so application of plant
micronutrients is necessary.
Water after becoming established:
twice a week to maintain the fruit crop.
Allow the soil to dry out between waterings. Water may be needed more often in extreme heat.
Inward leaf curling, when the leaves are uniformly green, is a sign of insufficient water. At
other times, deep water every one or two weeks in warm weather and every three to four weeks
Apply organic mulch inside the drip line and 8" away from the trunk to reduce soil evaporation
and reduce root zone heat and cold stress.
First Year Care:
Water at least twice a week, but do not overwater. The soil must dry out between waterings.
Remove any suckers growing from below the graft on the trunk.
Remove crossing branches and shape in winter. If pruning up from the bottom to expose the
trunk, the trunk should be painted with tree paint to avoid sunscald.
Litter: Fruit drop.
Cuttings grafted onto special rootstock. Rooted cuttings have very weak roots that do not
allow the plant to thrive, although they might do well in a container. Some, but not all,
varieties of kumquat seed may grow true to their parents.
The caterpillar of the Giant Swallowtail Butterfly resembles bird poop and has white and
black and/or brown splotches. On a large plant it will cause no harm. On a small plant,
relocate it to a large citrus. The fruit may need to be sprayed with a garlic and Habanero
pepper mix to keep insects away. See
Citrus: Diseases and Disorders
Uses: Ornamental, edible fruit, jams, marmalade.
Former scientific name: Fortunella.
Do you have additional information or a different
experience for this plant that you would like to share?
Email email@example.com. All contributions
are welcome and appreciated.