Pretender for the crown? ‘Monarch’ sunflower
I was going to write about Helianthus atrorubens ‘Monarch’ but I am now slightly concerned that my plant is not the true ‘Monarch’. I believe that the true plant has more than a single row of ray florets around the ‘flower’ and mine is more or less single. But in other ways it does seem to be correct. Helianthus atrorubens is named after the brown disc in the centre of the ‘flower’ and is native to woodlands in the SE USA. It is an invasive species and the plants grown are often hybrids involving H. pauciflorus.
The most common cultivars are ‘Gullick’s Variety’, ‘Monarch’ and ‘Miss Mellish’. All three seem to be confused and ‘Miss Mellish’ is often sold as ‘Gullick’s Variety’. I don’t feel I can be sure of what mine is unless I grew all three! ‘Gullick’s Variety’ should be 1.5m high with several rows of ray florets on flowers 12cm across. ‘Miss Mellish’ is 2m high with ‘flowers’ 10cm across. The ray florets are often twisted. ‘Monarch’ has flowers 15cm across and gets 2m high. It is notable for being invasive.
References I can find state that it has two rows of ray florets – or just one. What makes me slightly certain that I have the real thing is that it spreads like crazy and that the flowerheads are produced singly on the stems. My plant has stiff, slender stems that only produce four or five branches, well-spaced, with a single flowerhead.
My plant started last summer as a 1litre pot and is now a clump 1.2m across. It will have to be moved either next spring or a year later or it will take over the bed.
But, on the positive side, it has been self-supporting so far, even after a wet and windy week, and is making a bright splash of brazen yellow. The flowers are best appreciated by the birds since they are held horizontally and atop the 2m stems are hard to appreciate unless viewed from above.
The lack of posts this week has been, in part, because of business in the garden. We finally got the summerhouse up and painted. It is the main focus of part of the back garden which will be planted relatively simply – no helianthus ‘Monarch’ here (probably).
The ‘frames’ are made of spare skirting board and the lawn has been sown and I am pleased to say that the first shoots are appearing, six days after sowing.
All we need now is time to sit!
The Biking Gardener 
It’s so fun to read about my native plants being invasive elsewhere, given how many invasives we deal with here! I’m in NC so it’s very much “SE USA.” Watch out for those perennial sunflowers indeed–they’re thugs even here. I’m growing swamp sunflower “Helianthus angustifolius” which is said to be easier to control.
Your summerhouse is so nice! I’d screen it in here due to our out-of-control mosquitoes… I’m jealous!
I don’t think these perennial sunflowers spread by seed, but I could be wrong. They just spread fast through the soil. I may have to move them to the boundaries of the garden. If you love the thought of your natives going wild here you would be delighted to see railway embankments engulfed with asters (symphyotrichum) at this time of year. When I was living in London autumn was always the season to see lavender asters growing in the cinders and embankments on railway lines. The summer house should keep the wind off, if it comes from the north or east! Mozzies are not too bad here I am glad to say.
I love the summerhouse, a great design – open, yet sheltered.
thank you – yes that is what we thought. We didnt want it to turn into a shed! No possibility of storage. Time will tell!
It’s absolutely beautiful! Love the colours you chose too. With the great weather promised this week I hope you find the time to give it a good ‘christening’ !
Thank you. The inside is Seagrass which is a bit of a default colour for me – interesting but inoffensive. The outside is ‘Urban slate’ – charcoal grey really, which is not as severe as black and we thought would be ok with the grey paving.