Gardenia Growing Basics
If you live in the warmer regions of the country (USDA Zones 8-11) you can grow gardenias outdoors where they’re easier to maintain. Growing gardenias indoors during cold weather is where it gets tricky. The basic indoor gardenia needs are bright light, humidity, and regular watering. So try to put your plant in your sunniest window, set it on a saucer of rocks with water part way up the saucer to add humidity, and water it as soon as the top inch of soil feels dry.
Gardenia Leaves Turning Yellow
Naturally, some older leaves on gardenias may become yellow and drop off, particularly at the beginning of spring when the new leaves are on their way. This is normal so no need to start worrying. But if many older leaves are yellowing, your gardenia may be dying from root rot due to overwatering or poor soil drainage. Gently tip it out of its pot or if it’s outdoors, lightly dig away a little soil at the base of the plant. If the roots you see are brown and squishy, the party’s over. If you find white, firm roots, your plant still has a chance. The most likely reason for yellow leaves on gardenias is low iron. But guess what? You don’t need to add iron to solve the problem; you need to test the soil. Gardenias need acidic soil, which means soil with a pH between 5.0 and 6.5. This pH range makes iron in the soil available to gardenias. If the pH of your soil is outside those numbers, you can adjust it by adding an acidic fertilizer. Once your gardenia leaves are green again, use the fertilizer twice a month from early spring to late summer. Because of their exacting care requirements, gardenias are among the trickier houseplants to grow and can be challenging as outdoor shrubs, too. Knowing what they require to look their best, and correctly diagnosing any problems that do crop up will help you enjoy your plant for many years to come.
