Plant Doctor Archive

Ungainly Gardenia

MY young gardenia plant is looking very sad. I wanted it to grow in a pot by the front door so when it flowered there was a nice fragrance. It is in a large pot, but should I plant it in the garden? I even buried banana skins in the dirt around it as I heard they are good for gardenias. Can you help?

GARDENIAS make good container plants and, as long as you provide the necessities of life, you should be able to have one by your front door.

Firstly, they need good light. They don't do so well in deep shade, and full hot sun is also tough on them - dappled or light shade is ideal or shade for part of the day with some full sun. They also need a warm spot, sheltered from any chance of frost damage. Following our unusually frosty winter there are a few sorry-looking gardenias in some gardens, but most will recover.

Gardenias also need a potting mix formulated for acid-loving plants which you will be able to get from the local garden store. If the soil your plant is in is low in nutrients and you're not giving any supplementary feeding, say with a liquid fertiliser, then it may suffer from iron deficiency. The symptoms of this common gardenia problem are slow growth, few flower buds and yellowing leaves. Fortunately, it is relatively easy to cure using a solution of iron sulphate or one of the chelated iron products available in most garden stores. Follow the instructions and apply two or three times during the growing season if necessary.

Banana skins are a source of potassium, which is useful to all plants, and while they won't harm your gardenia they won't cure iron deficiency.

Like all container plants, gardenias also need regular watering in summer and, to encourage new growth and flower buds, I suggest you feed it regularly during spring and summer with a liquid fertiliser or apply a 6-9 month slowrelease fertiliser in spring.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.