Gardenias produce flower buds in late summer and fall for the next year’s blooms. To avoid removing these flower buds, wait to prune plants until after it finishes blooming in early summer. Gardenias typically need little pruning.
Improper pruning – When a gardenia plant is not blooming, the reason is often pruning too late in the season. Soil with an improper pH may be the reason when there are no blooms on gardenias. Extreme weather – Temperature extremes, either too hot or too cold, can also prevent blooming or cause buds to drop.
Most varieties of gardenia only bloom once a year, though breeders have developed a few varieties that can bloom more than once a year. Before pruning your gardenia, make sure to check that the variety that you own only blooms once or has completed its blooming cycle if it does bloom more than once.
Gardenia buds bloom as soon as a week. In general, it can be opened in about 20 days.
Light: Gardenias can handle full sun, but need protection from baking midday or afternoon sun in higher growing zones. North and east-facing exposures are ideal because they will receive bright morning light and some midday light, but won’t be in full sun all day or during the absolute heat of the day.
In addition to amending the soil with compost or aged manure, these acid-loving plants will appreciate coffee grounds, tea bags, wood ashes or Epsom salts mixed into the soil as well. Since they are rich in nitrogen, magnesium, and potassium, coffee grounds are oftentimes a more favorable homemade gardenia fertilizer.
Fertilize monthly, except when blooming with a fertilizer formulated for acid loving plants such as Miracle – Gro Miracid. This will encourage blooming. Prune your gardenia for size and shape in late winter or early spring. You can also cut off faded flowers to encourage additional blooms.
Gardenias need at least an inch of water a week, whether from rainfall or a hose. Apply mulch to a depth of two to four inches to help keep moisture in the soil and control water -hogging weeds. Don’t let the plants become completely dry before you water, and water regularly.
Indoors or out, gardenias thrive in acidic soil. Acidifying soil with vinegar, which is 5 percent acetic acid, can lower its pH to correct conditions for gardenias for a short time.
As for deadheading, gardenias drop their old flowers so deadheading is not necessary, but if for appearance’s sake you want to remove the spent flowers, you can cut the flowering stem back to a set of leaves anywhere on the stem. Wherever you cut, you’ll have one or two new stems emerging.
Gardenias are flowering evergreen shrubs hardy in zones 7-11. Their long lasting, fragrant white flowers bloom from late spring to fall. Each bloom can last several weeks before wilting.
Trim the branches by 2 to 3 inches just after flowering ends, from May to July. Do not prune any gardenia too late in the season, usually after August but as late as October in some areas. The resulting tender green shoots will not have time to harden and will be killed by a frost or freeze.
Misting the gardenia plant is not recommended, as this may cause problems with fungal leaf spot. The soil, which should be loose and organic, should be kept moist, but take care not to overwater. Monitor the soil frequently for moisture, and water thoroughly as the top inch of soil dries.
Irrigate your gardenias regularly to maintain moist soil, preferably through drip irrigation that keeps fungi-attracting moisture off foliage. Add a layer of mulch like pine needles to the area surrounding your gardenias without pressing the mulch against stems. Mulch improves water retention and keeps weeds at bay.
Water droplets that remain on the plant can also make gardenia flowers turn brown or develop spots. Pests – Mites are a common source of gardenia flower bud problems. Bud mites cause the tips of the buds to turn brown, and the buds fall off before they bloom.