Romantic Gardenia Thrives in May
Tara A. Spears
This standout warm climate plant has a flower that is renowned for its creamy white petals and romantic scent. The classic gardenia is one of the most fragrant flowers the home gardener can grow, but it presents a number of challenges. Gardenias are picky about their environment, needing a specific soil acidity, plenty of water and light, cool temperatures, and high humidity. Even more challenging, gardenias are also very vulnerable to pests. However, if you can overcome these challenges, you will be rewarded with beautiful, sweet-smelling blooms from spring through the summer. In Jaltemba Bay, the gardenias began to bloom after Easter and are still going strong: my young bush has averaged four open flowers plus new buds. I love to pick the flower when it just opens and float it in a bowl as an indoor air freshener.
Gardenia jasminoides is an evergreen flowering plant that originated in Asia and presently can be found growing wild in broad-leaved forests at low to medium elevations. Since the early 19th century the gardenia has been commercially cultivated and is highly prized throughout the world in floral arrangements and corsages. With its shiny green leaves and heavily fragrant white summer flowers, it i
s widely used in gardens in warm temperate and subtropical climates or as a houseplant in colder regions.
While gardenias are great for borders, as a stand- alone specimen, or in mass plantings, the most crucial step is how you plant it. Gardenia needs to be in full sun or partial shade. For best results in the subtropics, gardenias should be planted in a sunny location that is somewhat shaded during the hottest part of the day. Too much shade can reduce blooming and cause loss of the normal dark green color in leaves. This plant does like a good mulch to keep its roots cool in a hot climate.
Gardenias need to be in well-drained soil with good spacing between plants in order to have adequate air circulation in humid climates. Amend the soil with peat moss or compost to improve drainage and nutrient capacity. Dig a hole in the ground as deep as the root ball and twice as wide. If planting in a container, fill the bottom of the container with soil formulated for container gardening, leaving enough room for the root ball to be inserted in the container. Gardenias don’t respond well to root disturbance; take great care to ensure that the roots are not injured during planting. Water the plant deeply immediately after planting and daily for the next seven days. Water once a week during the dry season and be sure that the plant is in well-draining soil.
Each flower may last for five to seven days, but the bloom time can last for months with proper care. Only a few flowers are generally open at any given time per plant. Happy plants may bloom a second time in the fall. The locally available cultivars are perfect for our coastal habitat –and our warmer nights. Purchasing plants that are propagated locally ensures best results as the plants have evolved to the unique climatic conditions of this location. I’ve been thrilled for years to be able to enjoy the double blooming period.
Feed, Feed, Feed: Gardenias are heavy feeders and get yellow leaves easily. Proper fertilization is required for good growth and flowering production. Use a “complete” granular fertilizer containing nitrogen, phosphorus, potassium, and iron for best results. Due to the seasonal heavy rains during the key growing season, it is good to fertilize monthly between April and November with an acid fertilizer. Established gardenias require two additional fertilizer applications per year: February and October.
Throughout the bloom season, deadhead after each flower fades to encourage more blossoms. Shaping/ light pruning of gardenias keeps it healthy and preferred size. Pruning is best during August or September for optimal spring blooming.
Gardenias get yellow leaves due to an iron deficiency. Get some Ironite and give the plant a good drench taking care to avoid getting fertilizer on the leaves. If serious yellowing of the leaves occurs, add Epsom salts or iron sulphate to correct this symptom of iron deficiency. Pay careful attention to mixing instructions in order to avoid burning the roots.
Another problem in Jaltemba Bay area is the high ph level of the local water. Avoid using very hard water for your Gardenia. If soft water is not available, you can add some vinegar to the hard water to lower its pH; I just use bottled water to save time.
A common Gardenia problem in high humidity areas is ‘Black Sooty Mold’. This is an organism that lives on the honey dew secreted by aphids. The black substance does not hurt the foliage, but prevents the leaves from getting sunlight reducing photosynthesis. Aphids suck the juices out of the stems, which can become a severe problem. Regular inspection helps control insects from getting out of hand. Proper treatment with insecticide is needed when pests become noticeable. Even if you do not speak Spanish, take an infected leaf to one of La Penita’s agricultural supply stores and they will direct you to the appropriate product.
In spite of Gardenia’s finicky rep, the extra time spent keeping the plant healthy is rewarded with months of gorgeous sexy smelling flowers. Tropical breeze, tropical drink, and a flowering gardenia-doesn’t get any better than this!
