Planting in planters

When space is limited, such as on a balcony or a terrace, planting in planters is an interesting solution to grow some plants. Planters can be placed on the ground or suspended to create beautiful cascades of flowers.

Specificity of the culture in window boxes

A window box is by definition a container that is longer than it is wide, so it is possible to install several plants side by side. This specificity implies a choice of plants that require similar growing conditions, especially in terms of watering and exposure. It is out of the question, for example, to install cactus and impatiens together because these plants require opposite care. The result would be very quickly catastrophic!

Another parameter to take into account is the small volume of substrate for a number of plants that is often too large. Always keep in mind to install your plants at a reasonable distance so that they can grow and develop properly without competing too much.

For the same reason, the base substrate must be very rich and the fertilizers regular and sustained because the nutrients are quickly exhausted in such conditions. Let's add that watering constraints are also present, especially in the middle of summer, in hot, dry and windy weather. Depending on the plants, daily and abundant watering may be necessary!

Choose deep planters where the roots can properly develop.

Security

Often hung on the street side of a balcony, the planter must be firmly fixed to avoid accidents in case of a gust of wind. In this case, a light material should be chosen, again for safety reasons. Keep concrete or terracotta planters on the ground so that they do not hurt anyone if they fall.

How to plant in a planter?

Whatever the material chosen for your planter (iron, terracotta, plastic, stone, concrete...), drainage holes must be present at the bottom of the container. If they are not present, you will have to drill some.

Place flat pebbles on these holes to prevent the substrate from escaping and then pour a layer of clay balls or pebbles to ensure good drainage so that water does not stagnate at the roots;

Choose a very good commercial potting soil and add some compost and a bit of ground horn.

Pour a layer of this mixture on the draining bed and install your plants by respecting a good planting distance;

The neck of the plants should be about 1 cm from the top of the pot;

Fill in the remaining gaps with the mixture and pack the entire surface well;

Water thoroughly and add more mix if necessary.

Place your planter in its final location according to the requirements of the chosen plants.

Remember to water often and add liquid fertilizer regularly.

Growing lilacs in pots

Common in gardens as a lone subject or in compound hedges, the lilac can also find its place on a terrace or a balcony planted in a pot. Dwarf varieties are preferred to create beautiful scenes without taking up too much space, while still enjoying the wonderful fragrance of this shrub.

Which varieties for a pot plantation?

Choose preferably small varieties for a culture in pot. There are many cultivars not exceeding 1.5 m to 2 m in all directions. Among them:

• Syringa meyeri 'Palibin' with pink/blue flowers ;
• Syringa meyeri 'Josee' pastel pink;
• Syringa julianae 'Red Pixie' purple/wine-lily;
• Syringa microphylla 'Superba', otherwise known as 'Little Leaf Lilac' with pale mauve repeat flowering;
• Syringa 'Bloomerang Pink', a compact hybrid with repeat flowering of deep pink;
• Syringa persica Laciniata, the Persian lilac with sharply cut foliage and blue/mauve flowers, hardy to -15°C.

In what type of pot should I grow the lilac?

Choose a large pot with a minimum diameter of 40 to 50 cm and the same depth to give the roots room. A square or rectangular wooden pot, a large tub, or an unglazed ceramic pot will do the trick. Avoid bulging pots that are too difficult to unstuff and black plastic containers that heat up too much under the summer sun.

When to repot lilac?

Plant your lilac in a pot in autumn in the mildest regions, everywhere else, wait until spring or choose a hardy variety.

An annual topdressing with compost is sufficient for the first two years after planting, then a repotting will be necessary to renew the substrate.

How to plant lilac in a pot?

• The pot must be pierced at the bottom so that water does not stagnate.
• Add a layer of clay balls, gravel or small pebbles to the bottom of the pot to promote drainage, as the lilac hates having its roots constantly soggy. The drainage layer should make up about 20% of the volume of the pot.
• Prepare a mixture of ¼ good potting soil, ¼ garden soil, ¼ compost and ¼ coarse river sand.
• Pour a layer of the mixture at the bottom of the pot over the draining bed.
• Place the root ball and adjust the height, adding more mix if necessary, so that the neck of the shrub is 3 to 5 cm below the top of the pot.
• Fill in any gaps and pack well around the stem.
• Water copiously and add more mix if necessary.

Where to install a lilac in a pot?

A full sun exposure sheltered from drafts is ideal in the northern regions of the Loire. In the south, place your lilac in mid-shade in summer to protect it from the scorching midday sun. In winter, it can be placed in full sun, but be careful with watering in regions where rainfall is rare in winter!

How to water a potted lilac?

Like all plants grown in pots, lilacs will need more attention than if they were grown in the ground. So be careful, if you are used to growing it in the garden, it will require more care in a pot, especially in terms of watering in summer, which must be very regular so that your plant does not 'burn out', especially when exposed on a balcony in full sun!

In order not to make a mistake, never let the substrate dry on more than 3 cm of surface in summer.

In winter, make sure it doesn't run out of water if it doesn't rain.

What fertilizer should I use for my potted lilac?

Prefer an organic fertilizer, less aggressive than a chemical fertilizer, it will be better assimilated by the plant with just as much efficiency and this, without weakening it. In March, scratch a mixture of crushed horn and dried blood at the foot of the shrub or pour a handful of organic granules on the surface of the mixture. As it is not afraid of limestone, you can add a handful of chimney ashes at the end of winter, the blooming will only be more opulent!

How do I prune my potted lilac?

Smaller varieties grown in pots are only moderately pruned. The removal of wilted inflorescences in spring and autumn on remontant varieties constitutes the major part of the pruning operations. If necessary, it is possible, still after flowering, to remove dead wood and to aerate the silhouette a little by pruning the branches that cross in the center of the shrub and by reducing some branches by 1/3. Be careful, because lilacs bloom on the previous year's wood. If you prune too late and too short, the blooming may be compromised!

The culture of cycas in pots

Cycas is a popular indoor or patio plant when grown in a pot. With a short trunk and beautiful glossy foliage that makes it look like a palm tree, cycas is an easy plant to grow.

A primitive plant

Cycas are primitive plants belonging to the Cycadaceae family. Neither ferns nor palms but intermediate between the two, they grow naturally on rocky slopes or in dry, open forests in Australia, Japan, Madagascar and the Pacific Islands. The genus is composed of about fifteen species of which Cycas revoluta, and Cycas media, which are the most commonly cultivated.

Very ornamental, these plants are however cold; they will be planted in the open ground only in regions where frost does not occur. That is why, a culture in pot is recommended everywhere else in order to be able to winter the plant out of frost during the cold season.

How to plant cycas in a pot?

1. Choose a large enough and heavy enough container so that the plant does not tip over. The container should have a hole in the bottom to prevent the roots from rotting.
2. Place a pebble at the bottom of the pot and pour a good layer of clay balls to ensure good drainage (about 20% of the volume of the pot).
3. The nature of the mixture is very important in the culture of cycas; simple potting soil will not be sufficient because it needs a very rich substrate. Make a mixture of clay garden soil, compost, coarse river sand and pine bark. Add a little charcoal powder to this mixture.
4. Spread a layer of the mixture over the clay balls and place your plant in the center of the pot.
5. Pour the mixture around the root ball to fill in any gaps and pack the soil around the stipe.
6. Water copiously and add more mix if necessary.

How to grow cycas in a pot?

Cycas need bright light to grow well. Place it in a winter garden, a veranda or a bright apartment. Shade the windows during the hottest hours of the day if they are facing south.

In the summer, when frost is no longer a concern, you can gradually bring your plant out into the sun on the terrace or balcony. It will spend the summer there and will then be brought back before the first frost.

If you choose to grow your plant outdoors all year round, remember to protect the pot with bubble wrap and the aerial parts of the plant with a winter veil if you do not live in a privileged region.

As far as watering is concerned, cycas needs water regularly during the growing period but let the mixture dry on a few centimeters before watering again because this plant hates having its roots constantly bathed.

In winter and outdoors, let nature take its course. Indoors, water every 15 days and allow a short dry period during the coldest months.

A repotting may be necessary every 4 years in spring in the same type of mixture. If the subject becomes too big to be repotted, be satisfied with a surfacing with compost and crushed horn powder every year.

Growing boxwood in pots

An easy to grow shrub that always stays green, boxwood can also be planted in pots to decorate a terrace or balcony. The icing on the cake is that it can withstand most exposures and can even be sculpted into a topiary!

A precious shrub on a terrace

Boxwood (Buxus) is a hardy evergreen shrub belonging to the Buxaceae family. Native to the Mediterranean basin, it gives off a characteristically pleasant scent. Its small leaves form a compact clump that can be pruned into a ball, spiral or cone shape. It is therefore an ideal subject for a contemporary terrace as well as for a classic style balcony.

Planting tips

One important thing about boxwood: it hates having its feet in water! Choose a terra cotta pot with a hole in the bottom. Unglazed terra cotta allows for gas exchange and retains much less moisture than plastic pots.

Place a drainage bed equal to 20% of the volume of the pot at the bottom of the container. It will be made of gravel, clay balls or small pebbles.

Place a geotextile film on the drainage bed, followed by a layer of potting soil with ground horn powder.

Soak the root ball of your box tree for two hours in a basin of water before planting in order to rehydrate it and facilitate its recovery.

Place the roots on the substrate and fill in the vacant space with the same mixture up to the plant's collar. Pack and water.

Growing boxwood in a pot

For pot culture, choose a dwarf species such as Buxus microphylla, of which there are many varieties and cultivars. Boxwoods are equally at home in semi-shade or full sun. Be careful, because in the hottest regions, it will prefer half-shade in summer. During this period, it will be necessary to water it often because the culture in pot has this particularity to ask for waterings more sustained especially in period of strong heats and of big wind. Never leave water in the cups and wait until the root ball is dry on the surface before watering copiously again. In winter, natural rainfall should be more than enough, except in case of exceptional drought.

Boxwood is an easy shrub: it tolerates frost, pollution and even lack of water if it is not constant. Slow growing, repotting will only be done every 5 years. A surfacing every year will however be welcome. As for the famous pruning, it is done twice a year, generally in May and September, to keep the shrub in good shape.

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.