In A Cold Climate
There are many types of jasmine and most of them prefer warm weather. I love jasmine and refuse to be deterred by cold weather. When I lived in an apartment I grew a couple of Arabian jasmine (Jasminum sambac) on the windowsill as there was plenty of sun on that side. Now I’ve moved further north and have a garden, I grow more of them and more varieties too. But they live outside only in late spring until early autumn, then back down in the basement during winter.
In winter all my tropical plants stay under plant lights, with the timer set from 8 am to 7 pm. That includes the jasmines. There is no extra heat provided aside from a furnace that heats the house. The flower buds that developed while they were outside will still bloom under the lights. I stop feeding them when they are in the basement to prevent them from growing too lanky. Plant light isn’t the same as the sun, of course, so they still try to reach up to the lights, but still grow more slowly than they will outside under the summer sun.
Two problems with growing jasmine inside are spider mites and root rot. To get rid of the tiny spider mites requires monitoring, checking the leaves for them before there are too many of them. When my jasmine were small, I gave them a shower once a month. Put them in the bathtub and spray them with water both top and bottom of the leaves. This will provide them with moisture in a dry winter house as well as washing off the mites, if any. Once the plants get bigger, if I find mites, I spray them with insecticide soap (approved by OMRI for organic gardening use) and mist them with water once in a while. Too much water will make their roots rot. I will let the soil dry a little before I water them again.
When spring arrives and nighttime temperatures will stay above 50ºF, I take them outside, let them enjoy real sunlight. I start feeding them a month before I take them out. I also prune them at this time; cut out dry, weak, crossed branches or branches that are too long for my liking. I also remove most of the leaves from the plants, my grandmother’s method. Jasmine leaves grow in pairs, remove them alternately. This will encourage them to grow new leaves and flower buds. Then I feed them monthly while they are outside.
I let the flowers bloom on the plants if we plan to sit outside in the evening so we can enjoy their fragrance. I pick the flowers and keep them in the house, especially in the bedroom since the fragrance has a calming effect. I also put them in water to infuse their scent into it. Cold jasmine water is very soothing for a hot summer day.
With attention and care a jasmine plant will last for a long time. Some of mine are over 15 years old and still bloom profusely every summer.