Gardenia 'multiflora'

Class

Dicotyledons

Division

Angiospermae

Family

Rubiaceae

Order

Gentianales

Genus

Gardenia

Species

jasminoides

Description

An evergreen perennial shrub with a dense canopy dotted with numerous elegant flowers, either single or double, often intensely fragrant and cream-white in colour. It is sensitive to severe cold and sudden changes in temperature. There are varieties suitable for growing in pots and others for use in gardens in warm temperate climates, depending on the ideal conditions for growth and development. It requires acidic soil or growing medium and partial shade.

Variety description

A perennial ornamental plant, much prized for its elegant double flowers in pearly white shades, which are intensely fragrant and provide a perfect colour contrast to the glossy green foliage. It requires a bright position but one sheltered from direct sunlight, suitable relative humidity and watering that does not lead to waterlogging. It is strictly an acidophilic plant.

Curiosities and special features

The term Gardenia was given by Linnaeus in honour of the 18th century botanist and naturalist A. Garden, while the scientific epithet jasminoides refers to its similarity to jasmine flowers in colour and distinctive fragrance.

Origin and distribution

A species native to a range extending from Indochina to central and southern Japan, it arrived in Europe in the 18th century as an ornamental species, arousing admiration for the fragrance and elegance of its flowers.

Flower size

A variety with medium-sized flowers.

Leaf

The evergreen, glabrous and leathery leaves have a lanceolate, oval lamina.

Flowering period

The flowering period lasts from mid-spring to early autumn for a duration of between 90 and 120 days.

Leaf colour

Solid-coloured and glossy, creating a highly decorative colour contrast with the pure white of the flowers.

Plant height

The height of the plant varies from 0.5 to 1.2 m, depending on the location and the method of cultivation.

Lifespan

Perennial evergreen shrub.

Where to plant

In terms of the environmental conditions required, this plant is suitable for growing in large pots, in flowerbeds in temperate zones (subject to the temperatures described in the relevant section), on terraces, and indoors, provided the room is well-ventilated to encourage a longer flowering period

Stem

Shrub with a semi-woody stem and smooth bark.

Flower

The flower is peony-shaped, medium-sized, with an asymmetrical corolla. It is arranged in small head-like inflorescences. It flowers from mid-spring to early autumn, with a flowering period of between 90 and 120 days. It has sweet notes, is very fragrant and has an intense aroma. It attracts beetles and bees.

Growth

A variety with a compact and well-proportioned growth habit.

Plant habit

The developed habitus is bushy with dense, globular foliage.

Branching

The profuse branching results in a high density of leaves and flowers.

PH

Gardenias require an acidic soil or growing medium, with optimal pH values ranging from 4.5 to 5.8. A pH level above 6.0 can lead to iron chlorosis with leaf necrosis. Pay attention to the acidity level of the irrigation water to avoid fluctuations in pH.

Soil preparation

Depending on the climatic conditions at the growing site, the gardenia is mainly used as a pot plant. If the annual outdoor temperatures allow it, it is possible to grow certain varieties in the garden, provided the soil is properly prepared before planting. To this end, it is advisable to dig a planting hole of a size proportionate to the root ball, removing weeds and large stones, and to add organic or granular chemical fertiliser specifically designed for ornamental plants, breaking up the larger clumps to facilitate mixing with the soil and achieve a looser texture.

Sun exposure

Avoid direct sunlight, especially during the hottest part of the day, by placing the plant in partial shade or dappled shade, sheltered from draughts. It requires suitable, filtered light; a lack of light can lead to yellowing and leaf loss, as well as bud drop, whilst too much direct sunlight causes leaf scorch.

Ideal climate and temperature

The ideal temperature is between 20 and 25 °C. The survival temperature range is between 2 and 40 °C. In areas with very harsh winters, it should be brought indoors to a bright spot, but away from direct sunlight and heat sources; in summer, if temperatures allow, it can be kept outdoors in partial shade or light shade, sheltered from the wind. There are varieties of gardenia suitable for gardens that tolerate colder temperatures than others.

Use

It plays a key role, thanks to its pure white, fragrant blooms, in

ornamental use

Hardiness

A plant with medium to low hardiness.

Soil

The soil must be light and well draining, with an acid pH and rich in organic matter. For pots and planters, use a specific substrate for acidophilic plants.

Difficulty

Cultivation is moderately difficult, with an overall level of effort required that isaverage. Appropriate cultivation measures relating to the pH of the growing medium, exposure and watering will ensure suitable growth and flowering of high ornamental value.

Growing tips

Some growing tips to achieve the best growth and flowering results:

Avoid direct sunlight during the hottest part of the day Balanced fertilisation Keep the growing medium consistently moist It prefers water with low calcium carbonate content

Pruning

Remove any wilted flowers. Once flowering has finished, towards the end of summer, prune any overhanging branches slightly if necessary to maintain a dense, rounded crown.

Propagation

Multiplication is by apical cuttings and node cuttings.

Watering

Water the plant regularly with soft, lukewarm water, applying it directly to the soil or growing medium to prevent both the soil from drying out and waterlogging. Do not wet the above-ground parts or leaves of the plant, to avoid fungal diseases and leaf browning.

Fertilising

During the spring-summer period, apply a fertiliser for ornamental plants to the substrate to be diluted in the irrigation water without exceeding the doses and frequencies; in winter, if cultivated indoors, reduce the applications. Fertilisation should be carried out on moist soil.

Edibility for humans

Non-edible.

Tip

This is a highly ornamental species which, in order to achieve the best results in terms of vegetative growth and flowering, requires specific cultivation measures: an acidic substrate pH, and a location sheltered from direct sunlight and draughts. If purchased with buds that have not yet shown their colour, the plant must be kept at a minimum temperature of 18 degrees indoors so that it can flower in high humidity.