As you know, we both adore dahlias: sadly they don’t adore our garden. Dahlias appreciate a little elbow room and plenty of sunshine to grow well, neither of which they readily find at The Watch House. One recent garden visitor, pointing to Dahlia ‘Firepot’, exclaimed ‘everything looks so healthy …… apart from this poor thing!’. I might have been offended had I not agreed entirely: ‘Firepot’ looked sick and pale. It has taken me several years to come to terms with the changing conditions in our garden since I love to see those big, colourful blooms emerging from a mass of banana leaves. The truth is that behind those colourful blooms lie tall, straggly plants searching for the sun and often looking threadbare at the bottom.
Dahlia ‘Twyning’s After Eight’, D. ‘American Dawn’ and Aeonium ‘Zwartkop’ when the Jungle Garden was much sunnier
Gaining an allotment gave us the opportunity to relocate and build our dahlia collection successfully. We started off with a dozen varieties overwintered as tubers, including ‘Honka Fragile’, ‘Verrone’s Obsidian’, ‘American Dawn’, ‘Nicholas’, ‘Firepot’ and ‘Bacardi’, all old favourites. To these we added another sixteen cultivars from Sarah Raven which arrived as tubers in mid March. Being unable to control ourselves we then went on to place an order for a dozen cuttings from the National Dahlia Collection in Cornwall. At no stage had we made any plans for where to put them all, either in the earlier stages of growth or later on. This is very much the way things happen here and I imagine in many other gardens around the world. Hence one dahlia bed at the allotment turned into four, plus a row of pots and perhaps another one to come ……
It’s been eye-opening comparing the performance of our dahlias on the allotments versus the garden, and observing those grown from cuttings rather than from tubers. You may have seen our live dahlia tour on Sunday, which illustrates how healthy and happy they are looking in their new home. (The quality of the video is poor to begin with but improves later on. Sadly allotments do not come with WIFI!)
D.’Siberia’ 
D. ‘Honka Fragile’ 
D. ‘Twning’s After Eight’
Our allotment is bright and relatively exposed with free-draining, chalk soil. Our once lanky dahlias have grown stout and bushy thanks to several rounds of pinching out. This has resulted in them flowering a little later than anticipated, but they are more robust plants for it. The tubers we overwintered have made enormous, floriferous plants very quickly; one can spot the mature plants a mile off. But the dahlias grown from cuttings that didn’t arrive until early June have mostly caught up with with any tubers planted in March. Some are substantially bigger.
D. ‘Mango Madness’ 
D. ‘Ornamental Rays’ 
D. ‘Henriette’
We prepared the ground well before planting, digging in well-rotted horse manure and adding a generous scattering of blood, fish and bone at the time of planting. Subsequently I have given an occasional liquid seaweed feed, but there’s probably ample goodness in the soil to see them through to the autumn.
D. ‘Orange Pekoe’ 
D. ‘Waltzing Mathilda’ 
D. ‘Love of my Life’
So far we’ve kept on top of the deadheading. This will become a bigger chore as summer changes to autumn and our dahlias produce more blooms. Although better for pollinators, single dahlia flowers do not last long and need regular checking for spent blooms. I prefer to deadhead at the first sign of petals falling from the back of the flower – I have a real hatred of decay and disorder – whereas The Beau prefers to hang on and enjoy each bloom to the very last. Neither approach is wrong, the main thing is to stop the plant from producing seed and thinking it’s done its job.
D. ‘Penhill Dark Monarch’ 
D.’Jowey Winnie’ 
D.’American Dawn’
As in most aspects of gardening we are novices, not experts. Growing sixty dahlias on an allotment is very different to growing a dozen in pots in the garden; what we’d really like is a field full of them. We are learning all the time. Pest control has been easier than we anticipated, thanks to a population of frogs we have recently discovered living under our shed. They have been chomping through a large proportion of the slugs and snails that typically frustrate gardeners’ attempts at growing dahlias. We had a very brief plague of black fly which was swiftly dealt with by a rescue squad of ladybirds. Rather than taking action with chemicals I am glad we waited to see what our little red friends could achieve. As for earwigs we watch and wait, but none so far.
D. ‘Bloodstone’ 
D. ‘Bacardi’ 
D. ‘Taratahi Ruby’
Our support system is something of an experiment. Rather than staking each individual dahlia with a cane or post we have made a kind of framework using tree stakes and twine. I already regret using natural, cream-coloured sisal for the smaller beds as it is much too visible – you will see it clearly in some of the photographs. However green jute twine is easily snipped through whilst deadheading. Thanks to fine weather our dahlias have grown short and strong and we’ve had no wind or heavy rain to really test the efficacy of the framework. My hunch is that it could be a lot better, but it seems good enough for now. We’d love to receive tips from anyone who has to stake a lot of dahlias in a cost-conscious way.
D.’Purple Flame’ 
D. ‘Edge of Joy’ 
D. ‘Purple Explosion’
As I write about 60% of our dahlias are blooming. The other 40% are dahlias grown from cuttings or acquired in early summer. These will start flowering by the end of the month, continuing into November if we are lucky. I have managed to post a ‘Dahlia of the Day’ on my Instagram account for over a month now, and hope to be able to continue for another month without repeating myself too often. Many of those images are repeated in this post, but if you’d like to see more, please give me a follow.
D. Name Unknown 
D. ‘Magenta Star’ 
D. ‘Bright Eyes’
Dahlias are one of the most rewarding plants one can grow in a garden provided one can offer them the right conditions and are prepared to be vigilant when it comes to slugs and snails. They will flower for months on end, from June until the first frosts, never letting up. The number of cultivars runs into the tens of thousands with new introductions every year. Each country seems to have is own portfolio of dazzling dahlias so don’t be surprised if some of those I’ve mentioned are not available where you live.
Not all cultivars are good, but there are sufficient for you to find your own favourites. The only colour that does not feature in the dahlia colour palette is blue, and thank goodness for that! Dahlias will happily grow in pots provided they are well fed and watered. Although very far from being native, single-flowered dahlias are highly attractive to bees, supplying them with nourishment well into autumn.
D. ‘Bright Eyes’ 
D.’Honka Fragile’ 
D. ‘Twyning’s Smartie’
If you’ve not grown dahlias before, or feel inspired to grow more next year, then early spring is the time to place your orders for tubers and rooted cuttings. If you happen to be in Cornwall, then a trip to the National Dahlia Collection at Varfell Farm is a must. You’ll be met with a 2 acre display of 1600 or more dahlias which will dazzle you with the sheer variety and brilliance of this dazzling flower family. TFG.
Dahlia ‘Penhill Dark Monarch’
Categories: Dahlias, Flowers, Our Allotment, Perennials, Plants, Practical Advice
A gorgeous and inspiring post! Well done!
Thank you very much!
I have grown so few dahlias mainly because I don’t have enough sun for them. I have noticed that you don’t show any of the large dinner plate size dahlias. Do you not like them or are they more trouble than they are worth? I have seen a big yellow one used in gardens around here. They are stunning in the garden. Sometimes I wish I had less shade.
Hi Lisa. Actually ‘Mango Madness’, ‘Purple Explosion’ and ‘Penhill Dark Monarch’ are all whoppers! We also have ‘Labyrinth, ‘Spartacus’ and ‘Islander’ all due to bloom imminently. I like them more in an allotment setting than a garden.
I think shade has many advantages, but certain plants won’t tolerate it unfortunately. I guess we just have to accept our limitations.
No doubt with all the sun and manure your whoppers are growing well. I fully agree that we need to accept our limitations. One is much happier when we do that.
Wonderful pictures. I tend to go for smaller-flowerd varieties, to pick for the vase, and I grew some cactus-flowerd ones from seed (Sarah Raven) this year, some of which have turned out to be gems. All of my dahlias are in pots on the cut flower patch; no room left in the garden! Great to see your garden featured in The Garden magazine this month too…..great stuff!
Thank you. Such a privilege to appear in The Garden, especially on the cover. I will be interested to see how our dahlias in pots on the allotment do compared to those planted in the ground. I’ll keep you posted!
Fabulous photos Dan. I suspect I have all the S&S and earwigs! I have to wonder how they manage at Varfell Farm!
Hi Dan,
I’m immediately gripped by longing to grow Dahlias seeing your gorgeous pictures! I used to have them where I worked and would sneak a colourful bunch home from time to time.
Reg. staking; our friend Mark Harman makes a lovely chestnut-and-wire spiral stake which works really well and blends in very discreetly. We sell them at Madrona Nursery, should you want to give them a try.
They sound perfect Ylva. I was thinking of popping over in the next 2-3 weeks. Are you open and around on Saturdays?
Hi Dan,
Having just watched your allotment video, the dahlias, looked fab. I have grown my first dahlia’s this year from tubers – Avon bulbs, Mexican star. I didn’t realise it smelt of chocolate. I shall go out this evening and have a smell! Will you be doing more videos? I do hope so.
I also love the Beau’s contributions and the allotment updates. You make a great team along with Max and Millie.
Best wishes and happy gardening,
Lucy Saxon
Sheffield
Thank you so much Lucy! You’ll find our first video about the Jungle Garden here: https://www.instagram.com/tv/CDYWj02Hs2n/?igshid=y9czh5aixsrs .The picture quality is much better than the allotment video I am glad to say. This Sunday at 9am BST we’ll be doing a live tour of the Gin & Tonic Garden if that’s of interest. The more the merrier! Avon Bulbs is an excellent source of bulbs and tubers. You’ll find the chocolate scent is very faint but it’s there if you sniff hard enough! Dan
Beautiful! 🌸
I grow various dahlias at work which is on chalk. I no longer lift them as with a good covering of mulch they stay quite happily over winter. My guess is that you will be able to do the same thing. They seem to flower earlier as a result. You have got a rather splendid mix and how many cuttings will you be taking?!
Second allotment will be needed!
Too many dahlias! Even in a large garden, it is too many to keep track of. When we add more, I would like to get a few copies of only a few different cultivars, so that we can grow them in rows or colonies. For our landscapes, too many distinct individuals would be lost in the crowd.
A truly fabulous post Luv luv luv. You are feeding my addiction for these gorgeous flowers. I have just dug up my tubers and split them. Not really sure I know what I am doing. Have ordered another 20 new ones….where am i going to put them all… Well Like you, I will sort it out when they arrive… so enjoyed last weeks tour. It was glorious. 💚💚💚
Hello there. Your Blog is a beautiful example of just how wonderful dahlias are, and allotments are the perfect place just as our Grandparents might have once grown them, and with so many glorious forms to choose from now how could it ever be thought of as old-fashioned. I grow a number of mine in with the vegetable beds.
I have a couple of suggestions (you may have already considered).
Re dahlia supports; a framework is definitely preferable I think rather than trying to stake individual plants, but almost impossible to hide whatever you use. Therefore, my thinking is to use something you don’t mind seeing. Have you thought of the extendable wooden trellis panels that concertina out when pulled from the corners? Some come ready made from roughly split hazel or willow poles, or with enough time and considerable patience it is possible to fashion your own version. Placed horizontally across the bed and secured to posts in the corners, (and perhaps half way along depending on size), they need to be put in place early on so the dahlias grow up through the diamond shaped gaps. Eventually the growth fairly obscures the trellis work. You could tier the height of these frames putting shorter dahlias at the front etc etc. Alternatively green plastic pea netting stretched horizontally between supports follows the same principle and is more flexible, but it is plastic, but can be re-used….
I haven’t been able to deter the tenacious earwigs, however, Slug/Snail preventive wool pellets absolutely work100%. Sprinkled thickly in a circular barrier around the emerging shoots of over-wintered crowns, not a single nibble detected. Unfortunately this is a costly product so I am only able to use it on a few of my absolute best favourites (oh no, which to choose?!!).
Your photos are gorgeous, you sure about the amateur bit? Best wishes.
A good gardener is always learning and forever an amateur. There’s too much to know to be a professional.
I absolutely love the concertina trellis idea. That is genius. I am finding twine has too much ‘give’ to be properly supportive. Fortunately our allotment is so open and sunny that every dahlia has grown low and strong this year. However I will be borrowing your idea next season.
As for wool pellets, I have not tried them myself but have heard wildly varying accounts of their effectiveness. Thus far we’ve not needed a deterrent as we have frogs living under the shed. Best wishes to you too. Dan
So true, I’m definitely a professional amateur! We used to have lovely frogs, but then inherited 3 feral cats from neighbours who moved away and left them, so now I have a garden full of cat poo (eugh) and dead frogs (sigh). Still got toads though (yay).
Wow!! So beautiful. All the flowers are so bright and colorful that feels like a peaceful place. Thankyou and keep sharing!
I love dahlias and it was so cool that you posted all those different kinds. Such a pretty variety of colors and shapes. envy your garden!
I may be commenting in the wrong place but I couldn’t find any contact info or comment function on the post I actually wanted to comment 😄 I am wondering if your pics of Hollyhill Serenity is from your garden and if it is from Halls of Heddon? The pictures from HoH looks very much different and not as gorgeous as your version! 😊
Hi Elin, all the photographs are from our allotment. Sometimes dahlias do produce variations in flower form and colour depending on the season and growing conditions. By the end of last summer Hollyhill Serenity was producing much smaller and yellower flowers, nowhere near as sumptuous as earlier in the year. Dan