Gardenia Care Guide: How to Grow Gardenia Bushes

Gardenias (Gardenia jasminoides), named after Scottish botanist Alexander Garden, are a type of evergreen shrub with dark green leaves and white flowers. Also known as cape jasmine, gardenias are part of the Rubiaceae family. These flowers give off a pleasant fragrant scent, making them a popular choice for houseplants or cut flowers. Gardenias are native to the tropics in Africa, Asia, and the Pacific Islands. In China, gardenias are used in herbal medicines. The flower’s fruits are also used in yellow dyes for clothing, particularly in Korea.

Popular gardenia varieties include:

1. 1. 'August Beauty': The white flowers on this gardenia plant have a rose-like appearance. It blooms in spring and early summer.
2. 2. 'Veitchii': This gardenia plant has rose-like blooms with a longer bloom time from spring to fall.
3. 3. 'Kleim's Hardy': The white petals on this gardenia are broad and spread out from a yellow center. It blooms in spring and summer.
4. 4. 'Frost Proof': This gardenia, also called the Grace of the South, is known for being frost-hardy. It has white double flowers.

Gardenias are a tropical plant and grow best in places with day temperatures of 65 to 70 degrees Fahrenheit and night temperatures of 60 to 65 degrees Fahrenheit. Most varieties grow best in USDA Hardiness Zones 8 to 11, though some can tolerate zones 6 and 7. If you live in a cooler climate, you can grow gardenias outside in the summertime, but take the plant indoors for the winter. Follow these tips for growing gardenias:

1. 1. Grow gardenias from seeds indoors. You can grow gardenias from seeds, but they will take two to three years to flower. Plant the seeds in a pot with a mixture of potting soil, peat moss, and perlite in the early winter. Place the pot out of direct sunlight and keep the soil moist. Germination should occur in four to six weeks. You can transplant gardenias outdoors in the springtime after the seedlings grow two to three leaves.
2. 2. Plant gardenias outdoors in the spring. You can buy a gardenia container plant from a local garden center and add it to your garden in early spring.
3. 3. Make space in your garden a gardenia bush. Dig a hole twice as wide and as deep as the root ball, and plant the gardenia so that the top of the root ball is level with the soil surface.
4. 4. Plant gardenias in acidic soil. Gardenias grow best in acidic soil with a soil pH between 5.0 and 6.0. Use soil that’s rich in organic matter such as peat moss or manure.
5. 5. Cover the soil with mulch. If you're planting gardenias outside, cover the soil with mulch layers to keep the soil moist and weeds at bay.
6. 6. Place the gardenias in a sunny spot. Gardenias grow best in full sun, but too much direct sunlight, especially in hot southern climates (zones 8 and higher), can burn them. If you live in a hotter climate, place the gardenias where they’ll receive direct sun in the morning and partial shade in the afternoon. If you live in a cooler climate (zones 7 and below), plant gardenias in full sun. Place indoor gardenias where they’ll get 6 to 8 hours of indirect, bright light.
7. 7. Water gardenia bushes with one inch of water each week. Keep the soil moist but not soggy, and make sure the soil is well-drained after watering. Water the bushes close to the soil—if you water the flowers, they will brown.

Gardenia bushes have particular soil and temperature requirements and need more maintenance than a typical garden shrub. Follow these tips to best care for your gardenia bushes:

1. 1. Fertilize: Fertilize the gardenias monthly in the spring and summer with a slow-release fertilizer.
2. 2. Deadhead: To encourage continuous flower blooming, cut off any faded or browned flowers below the leaf node. Prune any dead leaves or scraggly branches on the gardenia shrub after the bloom time. You can also prune the green foliage to keep the bushes tidy.
3. 3. Mist: Gardenias grow best in high humidity and will thrive with regular misting. If you're keeping a gardenia as a houseplant, place it near a humidifier.
4. 4. Repot: To transport your gardenia to a new pot, use a mix of two parts peat moss to one part potting soil and one part sand or perlite.
5. 5. Protect from pests: Gardenias can fall prey to several pests, including aphids, mealybugs, and whiteflies. You can treat these pests with horticultural oil or insecticidal soaps.
6. 6. Treat infections: Gardenias can also become infected with fungal diseases such as powdery mildew, which you can treat with neem oil.

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