I’ve had a letter from Leonard at Cosham who loves his flower borders. But like most of us he realises that nearly all herbaceous plants bloom for about three weeks and then there’s nothing but foliage.
He tells me he has overcome this problem by choosing plants such as hostas, ladies’ mantle and rodgersia because the foliage looks wonderful on all of those plants. He uses irises alongside each of them as the foliage then contrasts.
What he would like, however, is a border with flowers all summer, and asks what I would suggest?
First of all I do admire the ideas of a lot of landscape designers who do exactly the same things. This can often be seen in the show gardens we see at Chelsea Flower Show and Hampton Court Flower Show, both of which are well represented on television.
Before we move on, please bear in mind the importance of removing dead blooms regularly because this often encourages perennials to produce flowers later in the year.
It is possible to add plants to a border of perennials by adding annuals. Dead-heading is essential for flowers all summer. These are sown from seeds in February in the greenhouse and planted out at this time of year.
Seeds can also be sown right now in gaps in the border. One of the finest is called salpiglossis. This is a glorious annual, about 18in tall with flowers almost the same as petunia, but these are striped with rich blue, mauve and yellow stripes and patches. It’s rarely seen these days yet it’s more glamorous than an orchid.
My favourite is cosmos also known as cosmea. It is important to ensure the eventual height of the plant is understood because plants range in size from about a foot to three feet. In our border at home we have a scattering all through the border so there are blooms every day from now until the frosts arrive.
Cosmea are available in pots at garden centres. They are in bloom now so the right colours can be chosen. They will be tall and are simply knocked out of their pots and planted between herbaceous perennials.
I didn’t see a cosmea in any of the show gardens at Chelsea. It must be because none of the garden designers read my articles – or perhaps it’s because cosmea is so cheap!
My final suggestion is dahlias. Single blooms grown from seed are the cheapest, costing between 25p and 75p a pot. Heights vary and they will flower well all summer as long as dead blooms are picked off regularly. They are good for arranging indoors too but if you can get hold of a dahlia catalogue there are literally hundreds of varieties ranging from the tiny pom pom blooms right up to some as large as dinner plates.
I love the water lily-type blooms best; after that the cactus types. But as I often say, choose the ones you like the look of. But again, with dahlias, you will be planting them out now with the flower buds forming and they will be in bloom all summer as long as the dead blooms are removed regularly.
Were there any dahlias at Chelsea? Yes, hundreds in one huge display... and it got a gold medal.