Citrus made easy for growers, nurseries, and distributors

Volkameriana is the most common rootstock, but TreeSource offers others as requested by our wholesale clients.

Kumquats thrive in containers and can last for many years when containerized. Because the fruit of kumquats are small, they are well-suited for smaller containers and indoor growing. They do need a sunny window or solarium indoors, as they are a plant that likes being outdoors, but when it’s too cold for them to be outside, they do well indoors.

Kumquats are some of the most cold-hardy citrus trees available, capable of withstanding lower temperatures than many other citrus varieties. Mature trees can typically survive temperatures as low as 18 to 20 degrees Fahrenheit for short periods without significant damage. This resilience makes them particularly well-suited for regions that experience occasional light frosts.

Among the different types of kumquats, Nagami is considered the most cold-tolerant. It produces oval, tart fruit and has shown strong resistance to cold down to around 18 degrees. Meiwa kumquats, which produce rounder and sweeter fruit, are also hardy but slightly less so, usually tolerating temperatures near 20 degrees Fahrenheit.

It’s important to note that while mature kumquat trees can handle brief cold spells, younger trees are more sensitive and should be protected during freezes. Container-grown kumquats are especially vulnerable and should be brought indoors or placed in a sheltered area when temperatures drop below freezing. For in-ground trees in borderline zones, using frost cloths, windbreaks, or even strings of lights to provide warmth can help safeguard against cold injury.

Because of their cold tolerance, kumquats are a popular choice for gardeners in USDA Zones 8b through 11. Their ability to handle chilly weather extends the range of citrus cultivation into areas where oranges, lemons, or limes would likely fail without protection. This unique combination of flavor, ornamental appeal, and cold hardiness makes kumquats a standout choice for both experienced citrus growers and beginners looking for a hardy, low-maintenance fruit tree.

Caring for kumquat trees is relatively easy, especially compared to other citrus varieties. The key is to provide consistent sunlight, water, nutrients, and protection from extreme cold—especially in the early years.

Kumquats thrive in full sun, so choose a planting site or patio location that gets at least six to eight hours of direct sunlight daily. They prefer well-drained soil and benefit from slightly acidic to neutral pH levels. If planting in the ground, make sure the soil drains well, askumquats do not tolerate “wet feet.” For containers, use a high-quality citrus mix and ensure the pot has drainage holes. Water regularly but allow the top inch of soil to dry between waterings. Overwatering can lead to root rot, especially in cooler seasons. During hot summer months, you may need to water more frequently. Consistency is key—avoid letting the soil completely dry out or become soggy.

Fertilize regularly with a balanced citrus fertilizer that includes micronutrients such as magnesium, zinc, and iron. Begin in early spring and feed every six to eight weeks through the growing season. Reduce feeding in fall and winter when the tree’s growth slows down. Kumquats don’t require heavy pruning but will benefit from occasional thinning to maintain airflow and light penetration. Although kumquats are among the most cold-hardy citrus, young trees should be protected from frost. If temperatures drop below freezing, cover in-ground trees with frost cloth or bring container trees indoors or to a protected spot.

This depends on the product type. For Citrus Liners, a lead time of four months is all that’s required. For our Large Pot trees, the minimum lead time is one year. Kumquats do very well with our Small Pot product, and it is best to contact sales for information on lead time and availability for those. You can also check out our Availability List to see if there is product available for immediate shipment.