Gardenia

Gardenias captivate with their large, white flowers. We’ve compiled some helpful care tips so that your plants can thrive at home.

Carolin Lenzser Carolin Lenzser
Apr 09, 2021 02:43 pm
readtime icon 7 Minutes
Growth type
  • shrub
  • Small shrub
Growth height (from)
from 50 cm to 60 cm
Growth characteristics
  • bushy
Flower color
  • white
Flowering time (month)
  • July to October
Flower shape
  • Shell Flowers
Flower characteristics
  • strongly fragrant
  • slightly filled
Leaf color
  • green
page format
  • oval
Sheet properties
  • evergreen
Fruit color
  • yellow
Fruit shape
  • Berry
Fruit characteristics
  • toxic
Light
  • scattered light
Soil type
  • sandy to loamy
Soil Moisture
  • fresh to humid
ph value
  • weakly acidic to acidic
Lime compatibility
  • sensitive to lime
Nutrient requirements
  • nutrient-rich
Humus
  • rich in humus
Decorative or utility value
  • Flower Decoration
Use
  • Interior greening
  • Planters
  • Winter garden
Garden style
  • Pot garden
Origin

The gardenia (Gardenia jasminoides) belongs to the madder family (Rubiaceae) and is native to the tropical forests of East Asia. It is also known as cape jasmine. The entire plant is poisonous.

Growth

The evergreen flowering shrub has a bushy habit and grows up to 25 inches in pots. In this country, the gardenia only thrives as a houseplant, however, it can be kept outside during the summer months in very warm regions. It is often used as a free-flowering hedge plant.

Leaves

The glossy, dark green leaves of Gardenia jasminoides are oval and leathery. They grow 2.36 to 2.75 inches long and are evergreen. The leaves are oppositely arranged.

Flowers

If you want a houseplant that not only looks good, but above all impresses with a pleasant fragrance, a gardenia is a great option. The double-flowered, cream white bowl-shaped flowers give off an intense scent. They grow 3.93 inches to 4.72 inches in diameter. Gardenias flower from July to October. At the turn of the century, the gardenia was often worn in the buttonhole as a floral decoration on special occasions and was cultivated for this purpose in large numbers in greenhouses, especially in France and the USA.

Gardenia flowers
The gardenia impresses with fragrant flowers
Fruit

The fruit of the gardenia are yellow berries. The entire plant is mildly poisonous, however most of the toxins are found in the fruit. You should therefore be very careful if you have children or pets in your household. It is best to put gardenias in spots that neither of them can reach. Poisoning tends to cause gastrointestinal complaints with diarrhea. Due to this property, the plant is used as a laxative in Chinese medicine.

Location

Growing the plant indoors is not entirely unproblematic. Gardenias need a spot that is bright all year round, however they should not be exposed to direct sunlight for too long. If the plant is in a south-facing window and the sun shines for more than a few hours each day, it might need sun protection. The optimum temperature is 64.4 to 77 degrees Fahrenheit in summer and 50 to 59 degrees Fahrenheit in winter. The plant can also withstand temperatures of up to 64.4 degrees Fahrenheit in winter, but only in bright places. Besides the house, the gardenia also enjoys temperate .

Substrate

The potting soil for Gardenia jasminoides should be lime-free and have an acidic pH of about 5. If you’re unsure, it’s very easy to check this using a test strip from a specialist store. Rhododendron substrate or azalea soil also satisfy the requirements of gardenia.

Watering

Keep the gardenia’s root ball evenly moist, but waterlogging must be avoided at all costs. Besides watering the plant sparingly, it also makes sense to create a drainage layer in the plant pot. As a general rule of thumb, make sure the surface of the soil is slightly dried out before watering again. Only use room temperature water with a low lime content. If your tap water is hard, it should be softened first. This can be mixed with rainwater. Gardenias prefer a relatively high humidity, so, besides watering, you can also spray the plant. However, you should only do this before flowering, and during the budding stage in particular. The flowers should ideally not come into direct contact with water as this can cause unpleasant discoloration. The plant can be watered more modestly from fall, but should not be allowed to dry out, even in winter.

Fertilizing

Between March and August, fertilize gardenias every two weeks with a low-lime, acid-forming fertilizer at a low concentration. Azalea fertilizer or products for are suitable for this. You can also use a low dose of the nitrogen fertilizer ammonium sulfate several times a year. This is also effective at preventing yellow leaves and leaf drop.

Potted gardenia
An ideal spot for the gardenia is a bright location that is not exposed to full sun all day
Repotting

Gardenias should be repotted every one to two years with a suitable substrate. The ideal time for this is spring.

Pruning

Gardenias do not generally need pruning. It is, however, advisable to hard prune bare gardenias in spring.

Additional Care

Gardenias are not entirely undemanding in their care, but are worth the effort. Give them what they need and the plant rewards you with an abundance of stunning, fragrant flowers. You should avoid moving the plant or allowing the substrate to dry out, especially while the buds are forming, as this can cause the plant to drop its blooms. Strong temperature fluctuations can be particularly dangerous at this time.

Varieties

Anyone who finds the species that grow up to 25 inches tall too big, can try their luck with the variety ‘Radicans’. At 12 inches, they are only half the height, but grow more broadly. The flowers are significantly smaller than those of the species.

Gardenia flowers
The flowers of the gardenia look like a painting
Propagation

The flowering shrubs can be propagated from tip cuttings before the buds form in spring or in fall. Gardenia cuttings should be around 2.75 inches long. Dip the base of the cuttings in rooting powder before putting them in the substrate. This improves the growth rate. A moist peat/sand mix is a good substrate option. Place a plastic bag over the pot to protect against evaporation. Young plants thrive in a bright spot at room temperature, the ideal temperature is around 77 degrees Fahrenheit. Once they have taken root, they should be pruned strongly so that they branch well.

Diseases and Pests

A lack of light and very high temperatures can cause Gardenia jasminoides to drop its leaves and buds. If the soil is too cold or wet, yellow-white patches can appear on the leaves. Mistakes during cultivation can result in discolored flowers, this can be easily remedied by making sure that the flowers do not get wet during watering. You should also keep an eye out for infestations of scale insects. The pests can be identified by their flat, oval to hemispherical covering and are most commonly found on the underside of leaves. If you spot silvery speckles on the leaves, spider mites are wreaking havoc. Affected leaves dry out and then fall off.