Which plants belong to citrus?
Citrus plants (and citrus fruits) are for example: lemon, lime, citron, mandarin, orange, kumquat, pummelo and grapefruit. Less known citrus species are: ichang, trifoliate orange (Poncirus trifoliata), and australian citrus.
I encourage you to familiarize with more popular citrus species, as well as with those less known.
Which citrus species should I grow?
The choice depends on what you value most in citrus plants: ease of growing, decorative look, tasty fruits, or maybe frost hardiness?
Citrus plants that are easy to grow
Lemon, citron and lime are the citrus species which can bloom and fruit profusely. They handle indoor conditions and can grow fast, and thanks to these traits they can be recommended to beginners. Also kumquat and its hybrids, for example calamondin, produce lots of flowers and can set fruit even in unfavorable conditions.
Citrus Ponderosa (known also as Skierniewicka lemon) is undemanding, fast to flower and set fruit.
Decorative citrus plants
Many varieties of citron (Citrus medica) and bitter orange (Citrus aurantium) were bred or selected for ornamental purposes: there are many variegated varieties or cultivars with odd fruit shapes. Another decorative group of citrus plants are kumquats and their hybrids. Also the exotic looking australian citrus species are worth of attention.
Procimequat is a decorative kumquat hybrid. It bears plenty of small fruits.
Tasty citrus varieties
Citrus plants are best known of their tasty fruits. The species which are grown primarily for edible fruit, are well known: lemon, lime, mandarin, sweet orange, grapefruit, pummelo or kumquat, and their multiple hybrids.
If you are growing a mandarin, orange or grapefruit tree, it’s important to overwinter it properly. Otherwise, it may not flower the following year.
Karlik mandarin is a prolific variety. The fruits are seedless.
Frost hardy citrus
Citrus are associated with subtropical climate, however, a few citrus species handle freezing temperatures suprisingly well. The most frost-hardy citrus is the trifoliate orange, which can grow and overwinter in temperate climate. Other cold hardy citrus are: ichang and related species, kumquat, some varieties of mandarin and of bitter orange.
Multiple hybrids of the above mentioned species exist, some of which are also highly frost hardy.
Trifoliate orange stands out from other citrus because of its appearance and its frost hardiness.
Citrus species – read more:
If you’d like to know more about a particular citrus species, read more about it: