Arthur's Blog: Dahlias and Tulips in Bins

9th August 2016

Arthur's Blog: Dahlias and Tulips in Bins

I love containers within a garden. For the factory garden, the trick was finding something that matched the factory’s industry look. My mum always grew plants in dolly tubs but these vintage old dears now command a high price. In a corner of the factory garden when I arrived were two dustbins full of rotten corn. I emptied and washed them, then stood back and admired them – suddenly there was something solid amongst the vastness of the gravel. I realised that these would be the containers for the garden here, and they are now one of its most asked-about aspects. This blog is about how I plant them up seasonally.



The bins arrive shiny and fresh looking but within a year, they weather up nicely. Before filling each bin, I turn them upside down and then drill several holes into the base. The holes are essential, so that water doesn’t sit in the bin’s base. Soggy water leads to the rotting of bulbs over the winter. I fill the base of the bins with a deep layer (about 15 inches) of crocks to further aid the drainage of water. Broken bowls are in no short supply here but broken terracotta, roof tiles, gravel and even polystyrene all make good materials to use as drainage, in containers.



After the crocks, in goes the compost, by the bagful. The bins eat compost up and each takes a full 70 litre bag of multipurpose, then another few extra spadefuls. If I have it, I’ll mix well-rotted manure into the compost too as I’m filling the bins, so that the compost has an immediate, extra additive of nutrients. The plantswoman Carol Klein once said a very good thing that every gardener should give thought to: “I never feed my plants, I feed my soil”. This will show in the growth of your plants – feed the soil and you’re feeding the foliage and flowers, so try to add muck and mulches during the whole year when planting things both in pots and the open ground.



Right now the dahlias and cosmos within the bins are reaching their peak. Both of these plants, one being a half hardy perennial (dahlia), and the other being a half hardy annual (cosmos), like to be allowed to grow a large root ball and be fed often throughout the growing season to maximise their flowering. The growth size of the plants gives the needed scale from these containers – I don’t tend to like dinky, small plants, but lush towering scale.



I feed the dahlias every 2 weeks with a mushed up soup of smelly organic chicken manure pellets. These are solid when you buy them in pelleted form, but I soak them and then once they have turned to a soup, I’ll add more water to the bucket and pour the brown liquid full of goodness into the watering can to then water the dahlias with. In November, when the frosts blacken the dahlia foliage, I’ll lift all the tubers and over winter in the greenhouse in crates of dry compost to reawaken in March. Each bin will then be planted with about 30 tulip bulbs, which are over planted with wallflowers. Once the tulips have finished flowering, the bulbs are lifted with their foliage intact and dried off – some of which will be replanted, if they are still chunky enough – while the bins are replanted for summer with dahlias and other summer annuals. Each time the bins are replanted, I add manure and blood and bone feed to the soil, which in turn feeds the plants and the resulting flora display.



The dahlias in the bins this summer are a lovely bee-friendly, anemone type dahlia called ‘Totally Tangerine’. They have supporting foliage in the forms of trailing plectrathus, a tender perennial, and an annual grass called Panicum ‘Frosted Explosion’ that has beautiful firework-like, airy seed heads.

Happy gardening,
Arthur

9th August 2016