Gardenia : Greenhouse Plants
W – warm, minimum of 13°C (55°F) / T – tropical, minimum of 18°C (65°F)
These plants look so lovely when they are offered for sale in shops but never seem to live up to expectations when taken into the greenhouse or home. They do better when kept under tropical conditions but it is feasible to give them a minimum of 13°C (55°F) during winter when they should be kept a bit drier. The foliage is an attractive shiny green but tends to go yellow if not fed enough. They are also lime haters and this should be remembered both with reference to pottingand to water supply. Sometimes the yellowing of leaves can be attributed to this and a feed of iron sequestrine should work wonders. The plant most commonly sold is Gardenia jasminioides from China and Japan. It is grown for its beautifully scented double white flowers which turn a yellowy-cream as they grow older, G.j. fortuniana is the most often grown and flowers naturally in summer. The buds need a steady temperature of just above 15°C (60°F) to develop properly. Unfortunately, the flowers are produced sporadically so the plant could never be said to look spectacular. I prefer a similar plant called Ervatamia divaricata which is taller and less compact but much easier to grow, not fussy as to compost and freer flowering. This plant flowers on and off throughout the year with scented flowers of a purer white; the only drawback is that one is unlikely to see one outside of botanic gardens.