Some of the most memorable parts of a garden can begin with a single pot.
A terracotta container beside the back door overflowing with herbs. A great stone planter marking the entrance to a path. Tulips emerging from pots in spring, followed by summer flowers, then perhaps a small tree whose branches change with every season.
Containers allow us to garden almost anywhere.
They bring plants onto patios, steps and balconies, add height to borders and give us the freedom to grow plants that might struggle in the surrounding soil. They can create a focal point, soften hard landscaping or simply provide somewhere convenient to grow parsley within reach of the kitchen.
But choosing a garden planter isn’t only about finding something attractive.
The size, material and drainage of a container all affect the plant growing inside it. Get those things right and both the plant and the pot can become part of the garden for years.
Start with the plant, not the planter
It’s easy to fall in love with a beautiful pot and then wonder what to put in it.
Sometimes that works perfectly well. But if you’re choosing a container for a particular plant, begin by thinking about what that plant needs.
How large will it eventually become? Does it prefer moist soil or sharp drainage? Will it remain outside through winter? Does it need full sun, or will it be happier somewhere cooler?
A small pot might be ideal for thyme or a collection of spring bulbs but entirely unsuitable for a shrub expected to live there for years.
Likewise, a very large container can overwhelm a delicate little plant visually, even if there’s technically enough room for its roots.
The most successful combinations feel as though plant and pot were chosen for one another.
Size matters more than you might think
Plants growing in the ground can send their roots outwards in search of water and nutrients.
A container-grown plant can’t.
Everything it needs has to be found within the confines of the pot, which makes choosing an appropriate size particularly important.
Small containers dry out quickly during warm and windy weather. They also provide less insulation for roots during periods of extreme temperature and leave less room for plants to establish.
Larger containers hold a greater volume of compost and generally retain moisture for longer, making them particularly useful for shrubs, small trees and permanent planting.
But bigger isn’t automatically better.
Rather than choosing the largest container available, select one that’s appropriate for the plant and be prepared to move it into a larger pot as it grows.
And before filling an enormous planter, remember that compost and water add a considerable amount of weight. Decide where you want it before you start.
Terracotta: traditional and beautiful
Few materials look more at home in a garden than terracotta.
Its warm colour works particularly well with green foliage, herbs and Mediterranean-style planting, and older pots often become more attractive as they weather.
Terracotta is porous, so moisture can evaporate through the sides of the container. This can be useful for plants that dislike sitting in persistently wet compost, but it also means pots may need more frequent watering during hot weather.
Frost is another consideration.
Terracotta absorbs moisture, and repeated freezing and thawing can cause some pots to crack or flake. If the container will remain outdoors throughout winter, look for good-quality pots sold as frost-resistant and make sure water can drain freely.
A terracotta pot may require a little more care than some modern materials, but that’s part of its character.
Stone: a planter that belongs to the garden
Stone containers have a wonderful sense of permanence.
They suit entrances, terraces and formal areas particularly well and can gradually weather into the landscape, developing the patina that makes old garden features so appealing.
Their weight can also be an advantage in exposed positions where lighter containers might blow over.
That same weight, of course, becomes rather less appealing when you decide the planter would look better on the other side of the garden.
Position stone containers carefully before filling them.
Real stone can be expensive, but good-quality reconstituted stone can provide a similar appearance and is often more affordable.
Wood: warm, practical and versatile
Timber planters can sit comfortably in both traditional and contemporary gardens.
Large wooden containers are particularly useful for vegetables, herbs and larger plants because they can provide generous growing space without the weight of stone.
Wood is also a natural insulator, helping protect roots from rapid temperature changes.
Its lifespan depends greatly on the timber, construction and conditions. Constant contact with wet compost and poor drainage will eventually encourage decay.
If you’re buying a wooden planter, look for durable timber from a responsibly managed source and consider how it has been constructed and protected.
Wood will change as it ages, but weathering isn’t necessarily a disadvantage. In the right garden, it can make a planter feel more at home.
Metal: useful, but think about temperature
Metal containers can bring a crisp, architectural quality to a garden.
They’re available in everything from traditional galvanised finishes to contemporary designs and can be particularly effective against strong foliage or grasses.
But metal conducts heat.
A dark metal container standing in strong summer sunshine can become hot, potentially raising the temperature of the compost and increasing water loss.
Think carefully about where it will stand and what you’re planting in it. Larger containers generally provide a more stable root environment than very small metal pots.
Metal containers also need adequate drainage and, depending on the material, protection against corrosion.
What about plastic and composite planters?
Plastic containers have practical advantages that shouldn’t be dismissed.
They’re lightweight, usually retain moisture better than terracotta and are relatively easy to move. This can make them particularly useful for large containers that need repositioning or for gardeners who find heavy pots difficult to handle.
Quality varies considerably.
A well-made container can last for many years, while thin plastic may fade or become brittle after prolonged exposure to sunlight and frost.
If you’re trying to reduce the amount of new plastic brought into the garden, look after the containers you already own rather than replacing them simply for appearance’s sake. Reuse is often the most sensible option.
There are also increasingly convincing composite and recycled-material planters available, some designed to resemble stone or terracotta without the same weight.
Drainage is essential
Whatever material you choose, check the bottom of the planter.
For most outdoor plants, drainage holes are essential.
Roots need both moisture and air. If excess water can’t escape, the compost can become saturated and roots may begin to suffer.
There’s an old gardening tradition of putting a layer of broken crocks, stones or gravel in the bottom of pots to improve drainage.
It isn’t necessary.
A layer of coarse material at the bottom doesn’t make water move through the compost more effectively. What matters is having unobstructed drainage holes and using a growing medium suited to the plant.
A small piece of mesh or a single crock placed loosely over a particularly large hole can stop compost washing out without blocking the flow of water, but there’s no need to fill the base with rubble.
Save that valuable growing space for roots.
Choose the right compost too
The planter is only half the story.
What you fill it with matters just as much.
Short-lived displays of annual flowers have different requirements from shrubs or trees that may remain in their containers for several years.
For long-term container planting, a loam-based compost can provide useful stability and structure. Other plants may need a more specialist growing medium – acid-loving plants such as blueberries, for example, require conditions quite different from Mediterranean herbs.
Peat-free composts are widely available and choosing them helps avoid the environmental damage associated with peat extraction.
Match the compost to the plant rather than using the same mixture for everything.
Think about water before summer arrives
Containers depend on us for water far more than plants growing in open ground.
Even after heavy rain, a densely planted container may not receive as much water as you imagine. Leaves can shed rain away from the compost, while small pots can dry surprisingly quickly in warm weather.
Large containers generally make watering easier because their greater volume of compost holds moisture for longer.
Position matters too. Pots in full sun or exposed to wind will dry more rapidly than those in sheltered positions.
When watering, give the compost a thorough soak rather than repeatedly wetting only the surface, and check containers regularly during hot weather.
A saucer can sometimes help retain moisture beneath thirsty summer plants, but don’t leave plants that dislike wet conditions standing permanently in water.
Give permanent plants an occasional lift
A shrub or small tree can live happily in a container for years, but it can’t remain entirely untouched.
Over time, roots fill the available space and the compost becomes depleted.
Depending on the plant, you may eventually need to move it into a larger container or remove it from the pot, trim congested roots where appropriate and replace some of the old compost.
Container-grown plants also need feeding because nutrients are gradually used by the plant or washed from the compost during watering.
Think of a permanent container as a miniature garden rather than a piece of decoration. The plants still need soil care, water, food and occasional attention.
Use planters to give a garden rhythm
Once the practicalities are right, you can begin thinking about how containers contribute to the garden as a whole.
A pair of substantial planters can make an entrance feel deliberate and welcoming.
Repeated pots along a terrace can create rhythm, while a single large container at the end of a path draws the eye onwards.
Grouping containers often works better than scattering lots of individual pots around a space. Try combining different heights while repeating a material, colour or style to hold the arrangement together.
And don’t assume every container needs to contain an explosion of flowers.
A simple fern in a beautiful pot, clipped evergreen structure or a grass moving in the breeze can be just as effective.
Sometimes restraint gives a container greater presence.
Don’t forget winter
A planter that looks wonderful in June still has to survive January.
If the container remains outside all year, think about frost resistance before buying it.
Make sure drainage holes remain clear and consider raising large outdoor pots slightly on pot feet where this helps excess water escape.
Some tender plants will need moving to a sheltered or frost-free position for winter, so weight suddenly becomes important. A beautiful container isn’t terribly practical if moving it requires three people and a sack barrow.
For very large permanent pots, choose plants capable of coping with the conditions where the container will remain.
Planning for winter at the beginning can save a great deal of lifting later.
Buy less, choose well
Gardens have a habit of accumulating pots.
A few are bought for particular plants, others arrive as gifts, and before long there’s a collection of empty containers behind the shed waiting for their moment.
Before buying another, look at what you already have.
Old terracotta pots can be cleaned and reused. A weathered wooden container may only need a small repair. Even an unfashionable pot can disappear almost completely beneath the right planting.
When you do buy something new, choose a container that will last and that you genuinely want to keep.
A well-made planter can stay in a garden for decades, hosting many different plants during its lifetime.
A pot is a small garden in its own right
Perhaps that’s the best way to think about choosing a planter.
It isn’t simply a container for holding compost. It’s the boundary of a tiny growing environment in which roots need water, air, nutrients and enough room to develop.
Get those foundations right and you can concentrate on the enjoyable part: deciding what to grow.
It might be a pot of lavender humming with bees beside a sunny path, a Japanese maple bringing autumn colour to a courtyard or strawberries waiting to be picked outside the kitchen door.
Choose the planter for the plant, give its roots the conditions they need and allow the container itself to become part of the character of the garden.
Because sometimes an entire garden can begin with one very good pot.
Further Reading: My Garden Journal & Notes
