Louise Curley

30 May 2022 09:15

Container Refresh – Pollinator-friendly Container Plants


My pots of spring bulbs have put on a fabulous display of colour this spring, with tulips waking up the garden with splashes of orange, red, deep purple and hot pinks as they intermingled with the crisp whites and glowing yellows of daffodils. But as these have faded it’s time to think about what will replace them to provide interest from now until autumn.

I’ve been gathering in plants from visits to nurseries and through online orders so that I had something to replace the bulbs with as soon as I emptied the pots. This year I’m aiming to grow in my containers more plants that are attractive to pollinating insects. More traditional bedding or container plants such as petunias don’t produce much, if any, pollen and nectar which means while they might look good to us, they’re of little interest to bees and butterflies. So I’ve decided to try and create a display that looks good but that will also be abuzz with creatures.  

This year’s plants include: agastache, lantana, cosmos, linaria, scabious, salvias, erigeron, single-flowered dahlias and a compact buddleia.

The RHS website has a comprehensive list of plants that are pollinator-friendly and look out for a bee symbol on plant labels which indicates they plant is good for wildlife. A good rule of thumb is to select plants with daisy-like, open flowers where the centre of the flower is easily accessible for insects. Plants with tubular flowers such as foxgloves and snapdragons have evolved to attract bumblebees, and flowers with long, slender, tube-like blooms such as Verbena bonariensis are particularly suited to butterflies. It’s also known that bees see the colour blue more clearly than other hues, so purple-coloured salvias, lavender, catmint and hardy geraniums are good choices, but make sure you seek out compact cultivars suitable for container growing.

Once the bulbs in the pots have finished flowering I pull them out. The daffodils are replanted in the garden where the foliage is allowed to die back naturally, as this will feed the bulbs so that they can produce next year’s flowers. Not all tulips are reliably perennial, they can be prone to a virus called tulip fire, and they wouldn’t survive the winter if they were planted in the borders in the heavy clay soil in my garden because they need free-draining soil. All these factors mean I treat tulips as annuals, putting them on the compost heap once the flowers have gone over, and planting fresh bulbs in autumn.

I scoop out the old compost from the pots, spreading this as a mulch around the beds in the garden. This compost has been in the pots for over a year now so there are very few nutrients left in it, but the structure of the compost will help to improve the soil as it’s broken down by worms and other organisms. Then it’s time to refill the pots. I like to use a soil-based compost such as John Innes or topsoil mixed 50:50 with a peat-free compost. This provides nutrients over a longer period, and I’ve found adding the soil means the pots don’t dry out as quickly. Then it’s time for planting. Once everything is in place give the pots a thorough water, and do this at least once a week if the weather is dry. By midsummer it’s a good idea to provide container plants with some extra food, as they’ll be exhausting the nutrients in the compost. I like to use liquid seaweed feed but tomato fertiliser works just as well.