When you group pots to create a complete border with them, you can achieve the colour and impact of a herbaceous border in a smaller space and often over a longer time.
If something isn’t working, you can move it round or take it out and put something else in. And you can experiment with different colour combinations and looks.
Dan Cooper uses this technique to turn his 20ft x 30ft (7m x 9m) courtyard into a garden that has been featured on BBC Gardeners World and in top garden magazines.
And Dan’s own blog, The Frustrated Gardener, has become so successful that he has left his job working for a major retailer to start Dan Cooper Garden, selling his favourite garden tools, pots and accessories.
So I asked Dan to explain how to group pots into a border, and also to give us some practical container gardening tips.
At the time I visited, the pot border was a riot of tulips and daffodils, but later in the year, he changes it to a richly exotic ‘jungle garden’ look.
How to group pots – display tips
Dan treats the pot garden as a ‘theatre’. ‘Place the taller pots and plants at the back and the smaller ones at the front,’ he says.
And when it comes to which pot or plant looks best next to which, he advises you to experiment. ‘That’s the wonderful thing about a container garden. If you get something wrong in a border, or you don’t like what you’ve planted together, there’s not much you can do about it.
But when you group pots to create a border, you can move things around until you’re happy with the combinations.
‘Try not to put the same colours next to one another or the same kind of plants side by side.’
But repeat plants and colours. ‘We try quite hard to bounce the colours down the garden,’ he says. ‘So if we’ve got an orange flower on one side, we’ll repeat it a bit further up on the other. So your eye is drawn towards the end.’
Make sure you have some green in between the bright colours. ‘This is a densely planted colour scheme,’ he says, ‘It’s much more colourful than you would get in a garden, so you need some calming elements.’
Plant one kind of plant per pot
Dan doesn’t combine different varieties of plants in his pots. He says it’s easier to position plants when there’s just one kind of a plant in a pot.
‘Plant a single variety of, say, a bulb, and you can cram them in,’ says Dan. ‘You can move them around easily within the grouping.
And you get each plant absolutely at its prime.
‘And if you are growing bulbs that you want to use again for a later season, you’ll know which ones they are.’ (Dan puts labels in his pots, so he knows which variety of plant he’s got.)
This is a very different look from the compositions we’ve featured in the post on top plants for a brilliant winter container display, but different approaches work well for different situations.
But maximise the colour by planting lots in each pot
Dan fills his pots with plants – there’s no bare compost showing. ‘We’re quite extravagant with the number of plants we put in a pot.’
When planting bulbs, for example, he puts in ‘a minimum of 25 bulbs’ in a 12″-14″ pot, planting in two layers.
‘It ensures you achieve an abundance of colour in a small space,’ he says.
Limit the varieties of plants
There are around 100 pots in the garden, but Dan limits the varieties of plants. He tries to have at least two, and often four, pots of the same variety of plant.
He uses these to ‘bounce colour’ around the garden. If there is a brilliant orange tulip at one end on the left, they’ll site another pot with the same brilliant orange tulips further up on the right. ‘It draws the eye down to the end of the garden.’
He also says that too many different colours and varieties could be too much. It would be jarring.
Do you plant directly into the ornamental pots?
Dan plants bulbs directly into their final pots, planting from September to December, ‘as pots become free.’
Although there is a second small garden on the other side of the building, it’s also very limited in space, so there’s very little space to store unused pots. Most of the 100 pots are replanted at least twice a year, and are on show in the garden.
He also plants about 10% extra into plastic pots, so he has extras to fill gaps.
Use a slow release fertiliser when planting up pots
It’s important to use a compost that’s formulated for growing in containers, as garden soil won’t have the right nutrients. Composts I’ve used successfully for containers include RHS Melcourt Sylvagrow Multi-purpose peat free compost.
Dan uses slow release fertiliser granules, which he adds when he plants up the pots. ‘The nutrition in the compost will only last a few weeks,’ he says. This is something I frequently forget to do, which means I have to feed my pots weekly with a liquid seaweed feed. So it really does save time to use the slow release granules.
How to water large groups of pots
Dan doesn’t have an automatic irrigation system, so he waters the pots manually.
To reach pots at the back, you need a long spout on your watering can or a similar attachment for your hose. They’re called a Spray Lance or Watering Wand.
Aim to soak the compost when watering rather than sprinkling water generally over the foliage.
If you group pots closely together, it helps prevent them drying out because it reduces transpiration. Dan points out that the foliage from each pot protects its neighbours from evaporation.
Start watering spring pots in early spring if the weather’s dry – twice a week, then every other day in summer.
How to change groups of pots over from spring to summer
The changeover from the spring to summer display is part evolution and part revolution.
As hyacinths and daffodils go over, Dan takes those pots out and adds in pots of later flowering bulbs, or plants like aquilegia or nemesia.
That goes on until around early summer, when they complete the process with a changeover to the ‘jungle garden’. This has gingers, begonias and plants with large, luscious leaves.
Do you need pot feet or crocks?
Dan doesn’t use pot feet. ‘We’re in a dry part of the UK, and we want to retain water in our pots most of the time.’
(If you’re in a very rainy area, you may benefit from pot feet, but it’s often hard for rain to penetrate the dense foliage of a fully planted pot. So it’s probably more important to avoid putting your plant pots in saucers in that kind of a climate.)
There’s been quite a lot of research by bodies such as ‘Which’ and the RHS which found no improvement in pots planted with crocks over those without. However, you’re often still told to put crocks at the bottom of your pots. I asked Dan whether he used them.
‘I’m on the fence when it comes to crocks. I think they probably aren’t necessary, except to stop compost dropping out the bottom of pots. But we use moss if we can instead.’
When you group pots, how do you get to the back of the pots in the display?
Dan says that it’s important to work safely when dealing with pots. They’re heavy and reaching over to the back of a display can cause back problems.
If he needs access to a pot at the back, he moves the pots in front of it, then moves them back again. It doesn’t take long and can save many problems.
For more about gardening without injuring yourself, see this post on How to Prevent Knee or Back Pain from Gardening.
More container gardening inspiration
Claus Dalby is another well known garden expert who like to group pots to create a border. See dahlias, by Claus Dalby here.
And you don’t always have to group pots. You can use them as focal points or to fill a gap in your herbaceous border. See 5 ways to display garden planters in your garden. If you don’t want the bother of changing pots seasonally, then evergreen pots look very stylish and are very low maintenance.
And although they are not all evergreen, there are more low maintenance pot ideas here.