Growing azaleas and rhododendrons in pots

Rhododendrons and azaleas are the stars of the heathland plant family and are highly prized for their opulent blooms in pastel and bright colors. These excellent bedding plants can also be grown in pots on a balcony or terrace by following our advice.

Why grow azaleas or rhododendrons in pots?

There are several reasons for growing azaleas or rhododendrons in pots: soil that is too chalky, lack of space or simply the absence of a garden may lead to choosing this type of cultivation.

The importance of the container and the substrate

Rhododendrons prefer to be at ease in large containers, whereas azaleas can tolerate being a little more cramped, which is important when you only have a limited amount of space.

These plants are acidophilic, so they need a substrate with an acidic pH. Plant them in very good quality heather soil. Don't forget to drain the bottom of the pot (which should be pierced) with a good layer of clay balls to allow a good evacuation of the watering.

Specificities of the culture in pot

Be careful, these plants appreciate a humid atmosphere, that's why they are so beautiful in English gardens!

Place them in half-shade if your balcony is exposed to the South, especially in Mediterranean regions where they would soon 'fry'. Spread a good layer of mulch at the foot to avoid too much evaporation and water often, especially in hot and dry weather.

Remember to remove the faded flowers so that the plant does not get exhausted.

Don't forget to repot your plants in the spring in a new substrate, or simply surface if the pot is really big.

Ideal varieties for pot culture

Some rhododendrons can form real shrubs, so it is better to turn to dwarf species and cultivars, more suitable for pot culture. Among this vast genus there are species with evergreen or deciduous foliage, the former will ensure a beautiful decor throughout the year, so they are to be preferred.

Japanese azaleas have a compact habit and pastel colored flowers. For a spreading habit, choose the variety 'Pink pancake', or the more original 'Azuma-kagami' with its bright pink interlocking corollas. White azaleas always make an impact: 'White moon' with its wavy petals will be a delight.

Rhododendron 'Blue Diamonds' is appreciated for its evergreen foliage and mauve/blue bloom, while the scarlet red of 'Elisabeth' will delight those who love bright colors.

The more subdued 'Grumpy' in pink and cream, or the pristine white 'Porzellan' are great pieces, while 'Glowing Embers' will add a little pizzazz with its large orange-red funnel-shaped flowers.

Growing citrus fruits in pots

Citrus fruits are very cold plants; they cannot be grown in the ground outside of the very sheltered regions. Everywhere else, growing them in pots will allow them to overwinter under cover.

The choice of the container

Citrus fruits have extensive roots and do not tolerate stagnant humidity. Based on this observation, the choice of the container will be a large vat or a terracotta pot which favors gas exchanges. Water reserve containers should be avoided because they keep the soil constantly moist, which is not very suitable for the needs of these plants.

Wooden boxes that can be dismantled are much more suitable because they make it easier to unpack the plants when it becomes necessary to change the pot.

Consider placing your container on wheels, it will be easier to move.

A suitable substrate

As we have seen, citrus plants need well-drained soil to avoid suffering. It will be necessary to provide a thick layer of clay balls at the bottom of the pot to facilitate the water flow and to avoid the asphyxiation of the roots which is always fatal. The substrate should be composed of one part acidic soil for one part good potting soil to which you will add two handfuls of compost and ground horn powder.

Planting citrus trees in pots

Choose a young subject without any black trace on the foliage. The foliage should be shiny and smooth. Also check for the presence of parasites on the back of the leaves before buying. The roots must not form a bun or escape from the pot as this would compromise the recovery.

In the spring, when all risk of frost has been eliminated, prepare the planting of your tree. To do this, soak the root ball for one hour in water at room temperature. Spread a bed of clay balls at the bottom of the pot and a layer of substrate. Place the root ball so that the neck of the plant is flush with the surface. Top up with the remaining substrate and pack the soil around the collar.

Water thoroughly.

Maintenance of potted citrus

Throughout the summer, your citrus trees can be installed in the garden or on the balcony to take the sun. Frequent watering is necessary because the soil dries out very quickly in these conditions. Remember to add a 'special citrus fertilizer' every two weeks during the growing season.

The pruning of the citrus fruits intervenes after the bloom. It consists in clearing the center of the plant to let air and light penetrate and to avoid the formation of pest nests and diseases to find a favorable ground for their propagation. It is also possible to pinch the new shoots on young plants to encourage a beautiful branching in early summer.

In autumn, bring in your citrus fruits before the first cold weather in a room that is not very heated but always free of frost and where the light will be maximum.

Wintering of potted plants

As winter approaches, the winterization of non-hardy potted plants on the balcony or on the terrace must be considered. It is advisable either to bring them inside or to take some precautions to allow them to spend the winter. We offer you some advice that should be adapted to your situation.

The non-hardy plants are plants which do not support the frost of the winter. Some of them can withstand small frosts but they will most likely perish with a frost of several days, especially since in pots the roots are less well protected, or even directly exposed because they are in contact with the container and therefore with the outside.

There are several categories of non-hardy plants. The least tolerant to the cold are tropical plants such as hibiscus or orchids that you should bring in first as soon as the temperature approaches ten degrees, between mid-September and mid-October depending on the weather. It is advisable to bring them in not too late to avoid too much change in conditions between your terrace or your garden and your interior. This shock could be harmful. You will bring in this type of plants in a bright room that does not go below 10 degrees. A veranda would be ideal.

Cacti do not appreciate the combination of autumn rains and cold weather which causes them to rot. Bring them in at the same time as your tropical plants and place them in a cool room like a garage with a light source if possible.

The last non-hardy plants to be brought in are Mediterranean plants such as oleanders, pelargoniums, palms or birds of paradise. Wait for the first frost to protect them, between mid-October and mid-November. Place your potted plants in a cool, airy place like a cellar or a garage. A little light will be ideal especially for the species with evergreen and clear foliage.

For the pots that you cannot bring inside, protect them from frost by moving them closer to the walls of the house or place them in a corner sheltered from cold winds. Wrap the pots with newspaper or bubble wrap and place your plant under a winter cover, not a plastic bag that will prevent the plant from breathing.

For all these plants, watering will be limited to the strict minimum to maintain a very light humidity, or even absent as for cacti. Remember to air and open your garage at the first beautiful days of spring. Mediterranean plants will be the first to come out as soon as the frost is over. Tropical plants will wait for better conditions to come out.

Wintering balcony geraniums

The pelargoniums of our balconies, often wrongly named geraniums, require very particular care if you wish to have the chance to see them blooming again the following spring. They are not very hardy, and wintering will be necessary for their survival in most of our regions.

At the end of October, when the days get shorter and the cold weather becomes more penetrating, clean your plants by doing a drastic pruning. Do not hesitate to cut back the stems, even if they are still flowering, up to 20 cm from the base of the plant for the ivy varieties. Keep only one third of the height of the stems of zonal pelargoniums and large-flowered species. Don't be afraid to do this: this pruning will make your plant all the more vigorous when it comes back. Moreover, it will be an opportunity for you to offer cuttings to the neighbors, which is always a pleasure!

At the same time, check your plants for pests and diseases. Cut off any damaged or diseased parts and burn them so that they do not contaminate the compost. Be careful, after this operation, disinfect your tools with alcohol so as not to spread the diseases, and if a plant is too sick to be sacrificed, soak its pot in bleached water and rinse it before using it again.

Once cleaned, install your pelargoniums in a cool but frost-free place: a garage, a well insulated garden shed, or better still a slightly heated veranda will do perfectly. Be careful though: the room must have at least one window so that your plants receive a minimum of light to survive, otherwise you will have to install artificial lighting.

Remove all the cups that could maintain a harmful humidity at the roots level and stop watering. Watering will only serve to keep the plant alive as it enters its vegetative resting period. One watering per month should be sufficient, but be sure that the foliage does not wilt. A lack of water is preferable to an excess during this period.

When the weather is fine and there is no risk of frost, you can gradually bring them out into the light, so as not to burn them. Once again, clean the yellowed or diseased parts and repot them in a special geranium potting soil mix already containing fertilizer. Remember to provide good drainage at the bottom of the pot and water after repotting to settle the soil and prevent air bubbles from forming.

Your pelargoniums will then be ready to start a new life for an ever more flowering spring!

Please note that ivy-leaved pelargoniums are often less resistant than zonal pelargoniums. More light will be beneficial to them.

Miniature gardens, an invitation to travel

A corner of the balcony, a table on the terrace, a sideboard in the living room, a window sill... A few square decimeters are enough to invite plants and miniature decorations in your home and create real mini-ecosystems where gardening talents and artistic sense are combined.

Imagine

Imagine a humid tropical landscape with lush vegetation, the semi-deserts of South Africa covered with succulents, the garrigue and its paths leading through low walls and olive trees, the mountain cliffs with alpine plants in the smallest crack.

Can you imagine booking your plane tickets? Yes. But you can also keep your slippers on, move to the lounge, on the bay window side. On its curved plateau, surrounded by ferns, selaginellas, the ficus is a bit dull: a tropical shower with a sprayer will be welcome. A few meters away, new climate, under the south-facing veranda, succulents are blooming in a miniature scree. The terrace will protect a Mediterranean space, on its rocky plateau, bordered by a low wall, an olive tree will offer its shade to a 2 cm long bench. A toothbrush will be enough to clean it. For the mountaineers, a small piece of garden, a corner of balcony, will welcome a lauze where will develop miniature pines, saxifrages, androsaces, sedum.

Miniature ecosystems

It is possible to create miniature gardens featuring plants and decorations to represent any type of landscape or ecosystem. A fundamental principle not to be missed: choose your climate, tropical, Mediterranean, alpine... Which will correspond respectively to the heated space of the house, the veranda or terrace well exposed, a shaded outdoor space or an alpine greenhouse.

Another fundamental principle: the choice of plants. Each one must be adapted to the chosen environment, a fern from the Amazonian forests will not withstand the rigors of European winters, and conversely an alpine saxifrage will not withstand the heat of our interiors...

Third fundamental principle: small plant will become big... It is essential to know the development of the chosen plants to maintain a harmonious balance in your landscape. An aloe vera will hardly have its place in a semi-arid garden of 20 cm in diameter...

Last principle: respect the fundamental needs of your ecosystem, i.e. water, temperature and luminosity which must correspond to the mutual living conditions of your plants.

An easy maintenance, generally

Easy... by the size of the tools. Small tweezers to clean plants, fine scissors to contain them, a sharp knife to cut the roots of unwanted guests, a 2-liter watering can, a sprayer, and a seat at garden height. Properly cared for, plants will continue to grow, more or less vigorously depending on the species. It's up to you to choose, to prune, to limit, to favor one or the other, to perpetuate the same balance, to move, to cut. In short, to make your garden live.

But everything can fail, and your tropical garden can turn into a deplorable mineral desert. Once you have chosen your location, near the living room window, far from the heating, and selected your plants, Ficus retusa, bromeliads, selaginellas, you can start watering. It must be copious, like a good tropical rain. In between, you will have to keep your substrate slightly humid, with a dry environment, regular sprays will be welcome. So for each environment, semi-arid indoor or outdoor, alpine, Mediterranean, the maintenance will have to meet the specific needs of your ecosystem.

An original creation

Once you have mastered the technical requirements, it's time to be creative. Composing a miniature garden is similar to designing a painting: strong points, vanishing lines, volumes. Foliage and flowering colors. All in three dimensions. And there is also a fourth dimension: time. The plants change with each season, blush in the cold, bloom one in the fall, the other in the spring. To create with the living by offering the conditions of a perennial growth is to open a new door, a journey, at hand.

The power of plants, the gardener and the imagination

By listening to his plants, the gardener learns continuously, and offers them the best growing conditions. They then take over, grow, bloom and reseed. The dialogue is constant. Grouped together in a miniature garden, the plants will also interact with each other, sometimes competing with each other, but also helping each other, cooperating. And to harmonize, with imagination, in a reduced but abundant space. 

Some plants:

• Tropical gardens : Ficus retusa, Ficus benjamina, Ficus pumila, Selaginella, ferns, ...
• Mediterranean gardens : Crassula sarcocaulis, Delosperma, Sedum, Sempervivum, Bergeranthus, ...
• Semi-desert gardens : Cacti, euphorbias, caudex plants, ...
• Alpine gardens : saxifrages, androsace, armeria, Cotula hispida, Pratia pedunculata, ...

Winterizing a potted petunia

In summer, the many varieties of petunias never cease to embellish terraces, balconies and beds. To prolong the pleasure from the following spring, shelter your perennial petunias during the bad season.

Prune shamelessly

Petunias and especially the drooping varieties of Surfinias tend to form long, branched stems that are not very aesthetic and do not flower as much over time. They will start again the following spring. This pruning will also allow the plant to regain its strength, you will be surprised by the beauty of the foliage and the number of flower buds present.

You can therefore prune all the stems to about ten centimeters from their base without regret. Take the opportunity to remove all the dead stems at their base with a small scissor. Place all this plant waste in the compost.

Clean the pot

With a small fork, scratch the surface of the substrate to collect all dead leaves and other plant debris. If the pot is made of clay, brush the sides with a stiff brush dipped in warm water and white vinegar to remove lime scale and moss that may hide pest eggs or larvae. To clean plastic pots, a sponge soaked in the same mixture will be sufficient.

Also clean the cup and let it dry.

The choice of the room

The chosen room should be slightly heated but frost-free because the petunia is not hardy, i.e. it does not resist to negative temperatures. A temperature between 10 and 14 °C will be ideal for wintering. If the room is not very bright, it is not very serious but it should be well ventilated.

Wintering petunias in pots

Before putting your petunia in the wintering room, make sure that the plant is free of parasites. You can prevent this by spraying the plant with nettle manure. If the plant has parasites, treat it and then quarantine it before bringing it in. Parasites tend to reproduce happily, well protected from their predators and the weather, so be extremely vigilant!

Once your petunia has been winterized in the shelter, only water when the soil really dries on the surface (about every 10 to 15 days). Never leave water in the cup, the plant is in dormancy, its growth is slowed down and it would risk to rot by excess of water. For the same reason, stop all fertilizing.

After wintering

When the frosts are no longer to be feared, repot your petunias in a rich substrate and add dice of slow release fertilizer. Take them out to the garden and gradually reintroduce them to full sun. Start watering them regularly, especially if it does not rain.