How to prune a hydrangea?

A shrub with exuberant and spectacular blooms, the hydrangea is one of the best values in the garden. Over the years, it can lose its elegance or its vigor, so pruning will be necessary.

Hydrangea pruning in brief

Hydrangea pruning should be done at the end of winter in a rational way so as not to compromise the flowering which takes place on the previous year's shoots.

1. Cut off the faded flowers above the first bud under the flower.
2. Cut off dead and dry branches
3. Cut the stunted stems and those that cross to aerate the center.
4. Cut back very old stems to their base.

How to prune hydrangea?

There are several species of hydrangea, all of which are part of the Hydrangea genus.

The ball hydrangea sold in florists (Hydrangea macrophylla) is the most common one in gardens, which is the one we will deal with in this article.

This hydrangea blooms on the previous year's stems, so pruning should be light at the risk of not taking advantage of its beautiful bloom.

The pruning operation is done at the end of winter or at the very beginning of spring before the vegetation wakes up. At this time, the stems only have buds and remnants of last year's faded flowers. Start by removing these by pruning them just above the first bud present under the flower.

You will then have to give a nice aspect to the shrub, especially if it has not been pruned for a long time and that the branches form a dense vegetal jumble. To do this, cut off all the dead and dry branches with the secateurs. Take advantage of this to trim the weak stems at their base as well as those that cross each other in order to clear the center of the plant and thus provide it with better air and light penetration. This important step avoids the installation of parasites and limits the development of diseases.

As we have seen, it is not advisable to prune all the stems at the risk of not being able to enjoy the flowers during the summer. A selection must be made in order to ensure the renewal of the shoots, to give back vigor to the hydrangea while keeping a maximum of branches bearing flowers. If your hydrangea is an old subject, cut back the very old stems at their base. You will recognize them by their larger diameter and lighter color. Keep at least two thirds of the branches unpruned to enjoy a beautiful bloom.

Cutting back hydrangeas

Hydrangeas can be cut back on older plants that have lost their vigor and whose inflorescences become smaller each year. In this case, it is possible to sacrifice one year of flowering by cutting back all the stems to 20 cm from the ground. Again, prune just above an outward facing eye if possible to clear the center of the shrub. Scratch some compost at the foot of your hydrangea to help it start again.

Gardenia culture and maintenance

Gardenias: indoor plants

Gardenias are very common indoor evergreens. They are the ones that are offered, that are placed on a corner of the dining room table, and then die without us knowing why; maybe too much water, or not enough...

These are plants native to Asia that are kept indoors because of their relatively low hardiness. Moreover, we meet a lot of them in South Africa.

Hardy varieties of gardenias

However, in recent years, there are varieties of gardenias that are resistant to cold. Some can withstand temperatures as low as -12 or even -15°C. This opens new perspectives; no more plants that die inside. By installing them outside, in pots or in a bed, their culture becomes much simpler.

The outdoor gardenias are specific varieties. Among them, there are plants with small, medium or large development. The largest of the hardy gardenias is Gardenia jasminoides 'Summer Snow'. It is a very vigorous variety, whose large white flowers give off a delicious sweet scent.

Flowering of gardenias

Most of the time, gardenias bloom during the summer. It can extend from June to October, or even November, knowing that some varieties are more remontant than others (4 months of bloom for some; 1.5 months for others).

The culture of gardenias

Gardenias are heathland plants, so they do not like limestone soils. The ideal soil is an acidic and rather fresh soil. If you live in a very dry place, where the soil layer is shallow, it is necessary to enrich the soil with compost and install a mulch to keep it fresh.

In a calcareous soil, it is mandatory to add heather soil or Sequestrene (even in neutral soil) because gardenia can be subject to chlorosis (yellowing of the leaves).

In summary, the cultivation of gardenias requires :

• plenty of compost ;
• a mulch ;
• a fresh soil.

The right exposure 

• In the south of France: sun in the morning, shade in the afternoon;
• In the northern regions, in Brittany or Normandy: full sun.

The multiplication of gardenia

The gardenia can be sown (NB: it is not self-fertile). It can also be cutted in September on the semi-hardened stem, but the percentage of success is weak.

Flowering shrubs for winter

In winter, the garden seems to be dull. To bring a touch of cheerfulness, think of winter flowering shrubs, so you can still enjoy a beautiful show from November to March, despite the cold.

The flowering cherry tree

Installed as an isolated specimen to enjoy its splendor, Prunus subbhirtella 'Autumnalis Rosea' will be among the earliest to bloom. It blooms from November to March in successive waves of small, soft pink flowers at the rhythm of the warm weather. Its development being limited, it can be installed in small gardens.

Dogwoods

Cornus mas and Cornus officinalis are very easy to grow and offer the spectacle of their yellow flowers in February-March. They like most soils and are very hardy, neither frost nor snow can harm them.

Winter jasmine

Here is a shrub that likes the shade and blooms in the heart of winter. Winter Jasmine (Jasminum nudiflorum) displays small bright yellow stars on its bare branches. It tolerates most soils and is equally well suited to be trained against a wall or left free to cover a slope.

Viburnum

Viburnum tinus, known by its vernacular name of 'Viorne', has a compact habit and is covered with slightly fragrant pinkish-white inflorescences throughout the winter. For variety, consider Viburnum x bodnantense and Viburnum fragans, which will bloom from November to March. The berries attract birds!

Sarcococca

It looks like a boxwood with pointed leaves from afar, but it is in fact a Sarcococca, a shrub of limited size (0.50 x 1.50 m) which starts to bloom at the end of January with original and fragrant white flowers.

The mahonia

An original shrub with prickly, tiered foliage, the mahonia is covered from February onwards with crowns of spikes of yellow flowers with fragrances reminiscent of lily of the valley. This shrub is ideal as a defensive hedge.

Witch Hazel

This shrub with a flared habit and elegant silhouette is adorned with fragrant lemon-yellow or slightly orange flowers from January. Another attraction of witch hazel is its foliage, which takes on flamboyant hues in spring.

Japanese quince

There are many varieties of Chaenomeles. If you choose them well, you will be able to stagger the blooms from December to March with a palette ranging from white to red, passing through pink and orange!

Edgeworthia

This little known shrub deserves its place in gardens where the climate remains mild because it is not very hardy (from -5° to -10°C once well installed). From February to April, it produces clusters of fragrant white and yellow flowers. Some cultivars of the edgeworthia like 'Red Dragon' put the red in the honor!

Scented winter shrubs

Most winter flowering shrubs are divinely scented, discover their scents.

Scented shrubs for the balcony

Sarcococca humilis: this small evergreen shrub grows very well in a pot. It forms in a few seasons a nice compact clump with dark green and glossy foliage. Small discreet cream flowers are present all winter long in the armpit of the leaves. They emit a very powerful vanilla scent. They are followed by navy blue berries. H and E: 0,5 to 1 m.

Its needs: half-shade, shade. Fresh and humusy substratum. Slight pruning after flowering.

Daphne odora: it is the most perfumed of all the daphnes. Its light green evergreen foliage edged with cream is covered all winter with a generous bright pink bloom with flowery and spicy notes evoking jasmine, carnation and clove. H : 1,5 m. E: 1 m.

Its needs: half-shade, sheltered from draughts. Very well drained soil, cool in summer, rich in humus. No pruning required.

Scented shrubs for the terrace

Mimosa : belonging to the genus Acacia, this small tree prefers mild climates. Its clusters of small golden yellow pompons illuminate the winter decor. The scent is reminiscent of sugar and honey. H and W: 2 to 4 m. Its needs: full sun, well drained soil, not calcareous (the species retinoides, the "mimosa of the four seasons" tolerates a little calcareous). When the cold is intense, protect the mimosa with a forcing veil or put the pot in a clear, unheated room.

Skimmia japonica : this shrub with a compact and rounded habit offers a dark green, shiny and leathery evergreen foliage. The plant is dioecious. The flowering of the male subjects is more beautiful than that of the females. From February, small bunches of creamy star-shaped flowers with purple stamens emit a scent reminiscent of vanilla, lily of the valley and orange tree. It is the female plants which offer a splendid brilliant red fructification. H and W: 1 to 1,5 m.

Its needs: light sun, half-shade, fresh soil. Pruning unnecessary (slow growth).

Viburnum farreri : formerly named V.fragrans, this beautiful deciduous shrub is a real winter incense with notes of vanilla, honey and almond. The small clusters of pale pink flowers can be seen from autumn, accompanying us until early spring. They are followed by red fruits. H: 2 to 3 m and W: 2 m. Choose the cultivar 'Nanum' which reaches 1 m and is decorative all year round.

Its needs: sun (shelter from the morning sun, avoid eastern exposures), cool soil. Prune after flowering if necessary. You can also fall for the Camellia sasanqua (blooms from autumn to the middle of winter). Our favorites for the small garden

Daphne mezereum: this deciduous shrub with soft green foliage justifies its name of 'pretty wood' with its generous pink or purple bloom, which lasts several weeks from February to April. Its flowers scent jasmine but also hyacinth, carnation and clove. They are followed by small red drupes scarlet very toxic but appreciated by the birds. H and E: 50 cm to 2 m. Slow growth.

Its needs: light sun, half-shade. Well-drained soil but cool in summer. Does not like to be moved.

Witch hazel: the "witches' hazel" is a deciduous shrub with an upright or spreading habit that blooms in late winter. Its flowers in light sulphur yellow, copper or brick red pompons are scattered along the branches. Their scent is reminiscent of honey. For its more intense perfume, prefer the species H.mollis to the hybrids Hamamelis x intermedia. H and E : 1 to 2 m. Magnificent autumn coloring of the foliage.

Its needs: sun, half-shade, shelter from drafts, cool and acid soil. No pruning (slow growth).

Mahonia x media 'Charity' : this large erect shrub becomes rounder with time. It offers a very decorative evergreen foliage. The large, leathery, dark green leaves have very prickly edges. The very long flowering period begins in the heart of autumn and lasts until March. The large clusters of golden yellow spikes perfume the air, evoking the scent of lily of the valley. The flowers are followed by navy blue plum berries, very appreciated by birds. H and W: 2 to 3 m.

Its needs: light sun, half-shade. Fertile, fresh and humus soil. No pruning (slow growth).

You can also fall for the Viburnum carlesii (flowering at the end of winter).

Scented shrubs for the country hedge

Abeliophyllum distichum : often called white forsythia, this little-known deciduous shrub has an upright and flared bushy habit. It blooms very generously from February (or March depending on the climate). The clusters of white to pinkish white tubular flowers smell like almonds! They are followed by heart-shaped and winged seeds. H and W: 1,5 to 2 m.

Its needs: sun, half-shade, shelter of the cold draughts. Fertile and fresh soil. Pruning unnecessary (slow growth).

Chimonanthus praecox : this large deciduous and erect shrub deserves the name of "winter sweetness" that the English give it. From the end of autumn until March, it is covered with a multitude of small discreet bells, waxy yellow speckled with purple, which scent the air for meters around. Their perfume evokes honey and exotic fruits (mango, passion fruit, pineapple). H : 2 to 3 m. E: 2 m.

Its needs: sun, ordinary soil. Useless pruning (slow growth).

Corylopsis pauciflora : cousin of the witch hazel, this deciduous shrub with a flared habit blooms massively from the end of February. The small, drooping clusters of primrose yellow flowers have a flowery scent with fruity accents of sweet orange. Beautiful autumn foliage. H and W: 1.5 to 2 m.

Its needs: sun, half-shade, shelter from draughts, fertile, light, rather acidic and cool soil in summer. Pruning unnecessary (slow growth).

Lonicera fragrantissima : this shrubby honeysuckle quickly forms a large bush with a spreading or even drooping habit. The deciduous to semi-evergreen foliage is compensated by the long winter blooming whose sweet perfume evokes honeysuckle, jasmine and orange blossom. The small cream flowers are renewed from December to March. They are followed by translucent coral-red berries that are toxic for humans but appreciated by birds. H: 2 to 3 m. E: 2,5 to 3,5 m.

Its needs: sun, half-shade, well-drained soil. Pruning unnecessary except to limit development.

Viburnum x bodnantense: this winter viburnum forms a large deciduous shrub with a rather stiff upright habit. It can bloom from November to March even if it is very cold! Its small round bunches of soft pink flowers in bud and white when blooming are reminiscent of jasmine. H : 3 m. E: 2 m.

Its needs: sun, half-shade, humus soil, fresh in summer. Pruning unnecessary.

Viburnum x burkwoodii : this hybrid quickly forms a large rounded bush with shiny dark green semi-evergreen foliage. At the end of the winter, bouquets of pink and then waxy white flowers adorn the plant, diffusing orange blossom scents all around. They are followed by red fruits becoming black in autumn. H and E: 1,5 to 2 m.

Its needs: sun, half-shade, humus soil, fertile and fresh in summer. Pruning unnecessary.

But also: Mahonia aquifolium (flowering in March-April).

Deciduous or evergreen leaves

There are many types of trees and shrubs. Some lose their leaves in the fall, others do not. This difference in vegetation is very important depending on the use of the plant in the garden. It is best to know this when purchasing.

Evergreen trees and shrubs

They are ideal for creating privacy or windbreak hedges because they do not recede in the wrong season. They are also ideal for planting in isolation. An evergreen shrub will always have a more beautiful aesthetic impact than a subject without leaves for part of the year.

Evergreen plants renew their leaves gradually and over the long term, so they always look green. Generally, the persistence of foliage corresponds to an environmental adaptation. The leaves are tougher, often thicker too because the cells that compose them have reinforced walls. They had to adapt to the heat or the intense cold. Thus, shrubs originating from southern areas, with a dry and hot climate, have developed tough, often glossy leaves that limit evaporation to a maximum. In the same way, to fight against the cold, conifers have modified the structure of their leaves, which have become needles or scales that are very tough and resistant over time. The leaf area is thus reduced, which makes it possible to better resist the cold. The foliage is then renewed in stages spread over several years for some species. This is why it seems that these trees and shrubs do not lose their leaves.

The flowering of evergreen shrubs is sometimes less ornamental but that is the price to pay!

Deciduous trees and shrubs

In autumn, when the luminosity weakens, the leaves are no longer able to store and transform energy. Nature being well done, a thick layer will form on the petiole of the leaves preventing the passage of the sap. The energy storage is then done in the wood tissues and the roots. Leaves without chlorophyll and therefore without green pigment take on flamboyant hues. Only deciduous trees and shrubs offer such a spectacle, literally transforming the garden into a dream setting. Winter arrives next, it corresponds to the rest period, ideal for planting.

In spring, with the lengthening of the days and the heat, these plants resume an intense activity producing leaves and flowers. The show starts again each year in an explosion of colors and floral scents!

Did you know about the variegated foliage?

Some information common to shrubs with variegated foliage...

Why is my variegated shrub losing its colors?

If it is a variety marked with cream or white, there is a good chance that it is too exposed to the sun. Chlorophyll, which is a light-sensitive pigment, begins to dominate again. Transplant the shrub to the shade and you will see the variegation appear again. If it is a golden variegation, it is the opposite, because the yellow pigment needs a strong luminosity to acquire all its intensity. In the shade, the color becomes more of a lime.

Did you know?

• Evergreen foliage does not fall in winter (in this case, it is called deciduous). However, evergreen leaves are not eternal. It lives from 3 to 8 years depending on the species, the plant constantly renewing part of its foliage. Contrary to a deciduous, the evergreen does not undergo a total stop of vegetation during the bad season. It continues to live in slow motion, which requires it to be supplied with water all year round, a very common "oversight" yet sometimes fatal to shrubs grown in pots.
• Evergreen plants are generally cooler than deciduous ones (conifers are an exception). Most evergreen shrubs are found in tropical climates. The colder the geographic area, the fewer the native evergreens.
• The usually green color of the leaf is due to the predominance of chlorophyll, a blue-green pigment. But if other pigments such as carotenoids (yellow-orange, red-brown) and anthocyanins (pink, purple, red) are more concentrated than normal, the leaf becomes colored.
• Most variegation results from the partial disappearance of chlorophyll in the leaf blade. It is often the result of a mutation, which implies the obligation to multiply it by vegetative way (cutting, layering, grafting).
• The very discolored cultivars pose problems of propagation. Indeed, in some of them, the plant does not have a sufficient quantity of chlorophyll for a fragment of cutted branch to live in autonomy the time to take root. It is therefore necessary to multiply these plants by grafting, which results in a higher selling price.
• The botanical terminology distinguishes the different types of variegations. Margined ('Marginata') is bordered by a thin band of color. Maculated ('Maculata') has a large spot of color, usually central. Striated or marbled ('Striata') presents more or less fine and regular colored lines. Punctate ('Punctata') is scattered with small colored spots. Reticulated ('Reticulata') is decorated with a colored net, often following the pattern of the veins.
• The nomenclature not accepting any more Latin terminology for all the cultivars obtained after 1956, many are adorned with names with Anglo-Saxon consonance, because the breeders of plants seek an international career for their creations. The 'Gold', 'Silver', 'Cream', 'Rainbow', 'Harlequin', 'Chamaeleon', thus bloom on many plants.
• It is necessary to be wary of the panachures which can hide certain deficiencies or a bad adaptation of the plant to its conditions of culture. Some mottling is also due to viruses (but it is most often floral mottling, as is the case for tulips).
• Gardeners often like to invent words, so they call "suffused" leaves whose discoloration is finely and irregularly degraded by the presence of small green spots more or less dense. This type of leaves could also be called "sandy" as in Aucuba japonica 'Crotonifolia' for example. This characteristic is more common in perennial plants. It is also sometimes found in some flowers (iris and roses in particular).