Peter Dowdall: Container gardening creates miniature ecosystems

Irish Examiner

26-04-2025

There's a common misconception that gardening requires a great expanse of land, beds to dig, and borders to fill, but the truth is, some of the most satisfying and ecologically rewarding gardens I've ever seen have existed entirely in containers.
Whether you've a balcony, a courtyard, a few stone steps outside a terrace, or simply a windowsill that catches the light, there's always a way to bring life and biodiversity into your world through plants. And now, in mid-spring, as the soil warms and nature is wide awake, is the perfect time to begin.
Container gardening isn't just a compromise for those without space. It offers a unique opportunity to create miniature ecosystems that can be both strikingly beautiful and sustainable.
It's perhaps even more important to be aware of promoting biodiversity in small gardens and urban areas than in the larger spaces, as species are more at risk in urban areas due to habitat destruction and lack of food sources.
When done thoughtfully, a few well-placed pots can buzz with pollinators, support a host of beneficial insects, and even provide food and medicine for us humans. The secret lies in choosing the right plants and caring for them in a way that mimics, as best we can, the balance of the natural world.
When choosing containers, remember that bigger is often better. Larger pots hold more moisture and nutrients, and that translates to happier, more resilient plants.
Terracotta is classic and beautiful, though it dries out faster, so be prepared to water more frequently. Glazed ceramic pots retain moisture better and come in a range of colours that can complement the planting. Even repurposed objects, such as an old zinc bucket, a cracked chimney pot, or a wooden wine box, can be transformed into charming planters with a bit of imagination and a few drainage holes.
Now, the plants. This is where the magic really begins. In spring, there's a temptation to go straight for the brightest bedding plants in full flower at the garden centre. But I'd urge you to think a little deeper and choose plants that do more than simply look pretty. Go for those that support pollinators, feed birds, and offer some form of habitat or food source. With that in mind, herbs are a wonderful place to begin.
Thymus vulgaris, the common thyme, is an unassuming little herb and not only a culinary staple, but when allowed to flower, becomes a magnet for bees. Its low-growing, spreading habit also makes it perfect for trailing over the sides of a container, softening the edges.
Pair it with Origanum vulgare, wild marjoram, which provides both food for butterflies and a delicate haze of pinkish-purple blooms in summer.
If space allows, one of my absolute favourites for containers is Salvia nemorosa or Salvia officinalis, the ornamental and culinary sages. These sun-lovers provide bold spikes of purple, pink or blue flowers and are beloved by bees, especially in sunny urban spaces where nectar can be scarce.
Scented foliage adds another layer of sensory pleasure, and they combine beautifully with ornamental grasses like Stipa tenuissima for a naturalistic, movement-filled display.
Another underrated gem for containers is Erysimum Bowles's Mauve, a long-flowering perennial wallflower that buzzes with insects from early spring right through to winter. Its dusky purple flowers and silvery foliage make it a great choice for even the smallest balcony, where it seems to flower forever, and its resilience in drought or poor soil is a bonus for any gardener with a tendency to forget the watering can now and then.
No container garden is complete without a touch of seasonal plants. Spring bulbs can such as crocuses, muscari, daffodils, tulips and alliums, can all be planted in autumn.
At the moment, as we look toward summer, consider adding Calendula officinalis, the pot marigold. Its bright orange or yellow blooms are edible, medicinal, and cheerful, and it readily self-seeds in containers, often returning the following year in unexpected places.
One of the joys of container gardening is the ability to move things around. This means you can play with colour and texture throughout the year, grouping pots together to make ever-changing displays. You can shift sun-loving plants into brighter positions or shelter delicate species during a storm.
This mobility also makes it easier to experiment, which is something I encourage in every gardener, seasoned or beginner.
Try mixing edibles with ornamentals, purple basil beside trailing nasturtiums, strawberries spilling over the edge of a pot beneath a small standard bay tree. Let the combinations be as creative and personal as your taste allows.
Watering is the one chore that mustn't be forgotten. Containers dry out quickly, particularly in warm or windy spots.
Early morning is the best time to water, giving the plants a good drink before the sun is high. If you can collect rainwater in a butt or barrel, even better, it's softer and kinder to plants than tap water, and it reduces your environmental footprint just a little more.
Now is the time to start as we head towards May and summer proper. In a matter of weeks, bare soil and empty pots become lush with growth, alive with the movement of bees and hoverflies, the flutter of a butterfly, or even the rare visit of a goldfinch to seed heads you've left standing.