container dahlias | why sarah loves these
Sarah discusses her current favourite dahlias for pots, and how to grow and care for them for the most floriferous container displays.
This is my current favourite container dahlia. It’s called ‘Schipper’s Bronze’ named after a Dutch friend of mine called Dicky Schipper, and it’s this extraordinary colour that reminds me of rusty, crinkly tin roofs, there’s just no other dahlia like it, and it’s perfect set against this dark foliage, this rich sort of chocolate foliage. The longer I grow dahlias, the more I absolutely love them, and that’s because they just flower, and flower, and flower, and they come in an incredible array of shapes and colours, and they’re also, if you pick the singles like this one, they’re brilliant for pollinators.
Other really good dahlias for pots – ‘Honka Fragile’, which is the most extraordinary, starry, white with a slight purple edge, and it’s exactly the right size for a bigger pot. It gets to about 3ft and so it will need supporting in a pot, but it flowers and flowers and it just looks so serene and beautiful.
We love ‘Totally Tangerine’ here in a pot. It flowers from the earliest to the latest of all the dahlias that we grow, and so sometimes we can have ‘Totally Tangerine’ in flower in June here, and it will go on flowering until the end of November.
Another dahlia I love for pots is ‘Sarah Raven’, the one that we’ve bred. I also love ‘La Recoleta’ in a pot, it’s like 'Chat Noir’ but slightly smaller, and then if you want a massive whopper pot, there’s no doubt that ‘Soulman’, which is a beautiful crimson going to purple anemone-flowered variety is an absolute corker.
There are a couple of things that’s worth knowing about growing dahlias in pots. The first is that even one like this which isn’t so big, it only gets to about 75cm, is you still need to stake them, and we tend to use hazel here cause it’s just much more natural looking than bamboo canes, but we sometimes use bamboo canes if we run out of hazel.
And the second thing is you need to deadhead about once a week, once every couple of weeks, and with some dahlias it’s quite difficult to tell what’s a bud, and what’s a going-over head, so you can tell immediately by this is round, and that’s a bud. With this one, it’s slightly more pointy, but it’s got some petals, and this is actually an emerging bud, whereas if you can see this one, that’s sort of pointy, that’s a ‘going over’, so that needs to be dead headed, and you want to get the scissors and just cut immediately above a pair of leaves. So now I’ve removed the leader, what happens is all the growth hormone that was collecting in that hasn’t got anywhere to go so it pushes out the auxiliary buds, so this will form a flower in a week or two’s time, and then there’s another mini, tiny one down in here, and that will develop as well, and that will flower a month later. And also once then this develops, you can see there’s another auxiliary bud coming there, so by continually dead heading, you continue to perpetuate flowering.