Citrus microcarpa Seeds | (calamansi)
LATIN NAME: Citrus microcarpa
COMMON NAME: Calamondin
Plant Profile
Calamondin is a small evergreen citrus of gardens and windowsills, grown for fruit and flowers at the same time on the same branch. It reaches two or three metres in a pot and rather more in the open ground, with dense, fine twigs, small glossy leaves and a scattering of white, waxy flowers that scent a room. The fruits are the size of a large olive, orange when ripe, with a thin, sweet peel and a sharply sour pulp full of seeds. In the Philippines it is squeezed over noodles and into iced drinks, and in Florida and California it has been a porch plant for a century. It is a hybrid, probably between a mandarin and a kumquat, and it has no wild population anywhere.
Science & Biotechnology
Because calamondin is a hybrid, its genetics are a record of citrus history rather than a wild lineage, and genomic work places it close to Citrus reticulata with a contribution from Fortunella. Like many citrus it is polyembryonic, producing several seedlings from one seed, only one of which is sexual; the rest are nucellar copies of the mother, which is why seed-grown plants come true. That trait made citrus a classic subject in the study of apomixis and still makes it useful in rootstock breeding. The fruit’s acidity comes mostly from citric acid, and the peel carries limonene together with smaller amounts of sesquiterpenes that give calamondin its particular aroma, sharper and more floral than a lemon. Work on cold tolerance suggests the hybrid inherits the kumquat’s ability to survive a few degrees of frost.
Uses & Benefits
The juice is the point. It is sour enough to use like lime, and in the Philippines it goes into dipping sauces, marinades and the cold drink called calamansi juice, sweetened and served over ice. In Malaysia it is pressed into a hot drink with honey for coughs. The whole fruit can be candied, pickled or frozen, and the peel is used in marmalade where its sweetness balances the pulp. As a garden plant it is one of the few citrus that fruits well in a container, and it will flower and fruit more or less continuously if kept warm and fed. It is also a good conservatory plant for a cool climate: small, tolerant of pruning and generous with scent when it flowers.
Growing from Seed
Sow fresh seed, since citrus seed loses viability quickly. Use a free-draining mix of loam, coarse sand and compost, and press the seed one centimetre into the surface. Keep at twenty-five degrees with steady moisture; germination takes three to six weeks, and several seedlings may emerge from one seed. Pot on when the second set of leaves appears, using a citrus compost with added grit. Grow in full sun, water when the top of the compost dries, and feed with a high-nitrogen fertilizer through summer. In cool climates keep the plant above five degrees in winter. Pinch the tips to build a bushy frame, and expect fruit from the second or third year.
Our Take
A citrus that fruits in a pot and flowers while it does so. Sour, scented and worth the winter indoors.
Related Reading
If Calamondin appeals to you, these related plants are worth a look: