How to Grow Gardenia

Gardenia Magnifica (Gardenia jasminoides ‘Magnifica’) has a lovely soft bloom and is quite well-perfumed. It can grow up to 2.5 metres high and produces larger flowers compared to other Gardenia varieties and cultivars.

Gardenia Florida (Gardenia augusta ‘Florida’) can tolerate both part shade and full sun. It has large glossy leaves that have a lovely contrast with the soft flowers when they appear. Can grow to 1.5 metres tall and is great for soft and informal hedging.

Gardenia Radicans – (Gardenia augusta ‘Radicans’) is a smaller growing variety that grows best in full sun, but can still handle part-shaded conditions. This plant has smaller leaves than the ‘Florida’ and grows to about 0.5 metre tall and 1.5 metre wide. Flowers are small, but still fragrant. Great for an alternative low groundcover in garden beds.

Choose a spot in the garden that gets full sun to part shade, with well drained soil. Enrich the soil with Yates Dynamic Lifter Soil Improver & Plant Fertiliser. If the soil is clay based, add gypsum and fork in well.

Dig the planting hole twice as wide and to the same depth as the root-ball. Remove the shrub from the container, gently tease the roots and cut away any circled or tangled roots.

Position in hole and backfill with soil, gently firming down. Form a raised ring around the plant, creating a well so that water will go where it’s needed most. Water in well.

Mulch around the base with organic mulch like bark chips, sugar cane or pea straw, keeping it away from the main stems of the plant.

Feed every week with Yates Thrive Roses & Flower Liquid Plant Food.

• Mulch over the root system with an organic layer, milled cow manure is ideal but an organic mix such as pea straw will also suffice. 
• Make sure that potted gardenias, particularly, aren’t allowed to dry out between watering.
• In very dry climates it can also be helpful to mist spray water over the leaves on hot days, although not when the sun is directly shining on the plant.
• Remove spent blooms to encourage further growth.
• You can propagate these plants by softwood cuttings in autumn and winter. 
• Flowers are often used in weddings or as a fragrant cut flowers indoors.
• Great for therapeutic gardens for their lovely scent, soft petals and no tool are required to remove the dead flowers making it easy for anyone to perform this task.

As with most flowering plants, the best time of year to prune a Gardenia is just after flowering. Most Gardenias flower in spring and summer, so the end of summer or early autumn is generally best. Just make sure the plant is well watered before and after pruning, and feed just after pruning with Yates Dynamic Lifter Soil Improver & Plant Fertiliser.

Soon after planting, tip prune stems to encourage bushier growth. This is particularly important if you are growing Gardenia as a hedge. If you let your Gardenia grow naturally it might end up looking leggy and sparse and will require a harder prune to get it back to shape.

As with most plants, the best time of year to transplant is in autumn when the soil is at it's warmest. You can also transplant in spring when the weather starts to warm up.

Just make sure to keep the plant well watered in the days leading up to transplanting, prune off at least a third of the total foliage volume, and move to a position that has rich, acidic and well-draining soil.

Apply Yates Dynamic Lifter Concentrate as a foliar spray to help with reducing transplant shock.

The sticky, black, sooty stuff that is sometimes seen on the surface of Gardenia leaves is called Sooty Mould. Sooty Mould is a secondary disease caused by sap-sucking insect pests. The sap-sucking pest sucks out the plant juices, then excretes it as a clear and sticky residue known as "honeydew". This honeydew is used to feed other insects, such as Ants, in exchange for protection against predators. Leftover honeydew then sits on the surface of the leaf and encourages the disease Sooty Mould.

See How to Get Rid of Sap-Sucking Pests on Gardenias for treatment options.

There are a few reasons why this might be happening: lack of water, incorrect soil pH, lack of fertiliser, and Thrips.

Thrips are very small, long and slender pests that often hide in the flower bud. Grab a piece of paper, and shake the flower to see if any fall out. See How to Get Rid of Sap-Sucking Pests on Gardenia for treatment.

Gardenias are prone to a variety of sap-sucking pests including Aphids, Thrips, Whitefly, Scale, Mealybug, Two-Spotted Mite and Whiteflies.

All these pests can be treated with Yates Nature's Way Citrus & Ornamental Spray. This product Also controls Ants, and Sooty Mould which is associated with various sap-suckers.

Make sure you are feeding you Gardenia as plants that are malnourished are more prone to pests and diseases, and less likely to bounce back after an attack.

The most common cause for yellowing leaves of Gardenia is to do with the soil pH. Soil pH is a measurement of how "Sweet" (alkaline) or "Sour" (acidic) the soil is and is on a scale of 0 to 14. Gardenias need acidic soil between 5.0 and 6.5. If the soil pH is too high, then the plant can't access the nutrient magnesium which exhibits as a deficiency. Most of the time, there is plenty of magnesium for the plant, and the root cause is high soil pH.

Apply Yates Soil Acidifier Liquid Sulfur and gradually lower the soil pH until it is between 5.0 and 6.5.

Some soils can be deficient in magnesium, however, regular applications of epsom salts or Magnesium Sulfate can result in toxic levels of soil magnesium.

The best and safest thing to do to treat yellowing, or pale leaves for a gardenia is to treat the root cause of a high soil pH. See How to Acidify the Soil for a Gardenia.

The usual culprits for holes in leaves and flowers of Gardenia are Caterpillars, Snails and Slugs.

Spray plants with Yates Nature's Way Citrus & Ornamental Spray.

Sprinkle Yates Snail & Slug Bait around the base of plants.