Cactus-type dahlias grown by John Spangenberg await staging at the National Capital Dahlia Society Annual Show at Brookside Gardens. Picture: Adrian Higgins/The Washington Post

Washington - I was standing along the suburban Washington waterfront a couple of years ago when a Spanish galleon showed up, proving once again that if you wait long enough, everything comes full circle.

This is especially true in the gardening world. Houseplants, embraced by hirsute, plaid-draped baby boomers in the 1970s, fell into obscurity before being rescued in this century by millennials.

Succulents were once the domain of rock-garden enthusiasts - there is no more esoteric a subset of gardeners - but are now an essential part of contemporary urban life. Old garden roses are back and so is kale. What will be next? Carnations, snapdragons, Kentucky bluegrass? The possibilities are endless.

The dahlia, a tender perennial from the high plains of Mexico, sent Europeans into a frenzy of delight when it showed up in the Old World, quite possibly aboard Spanish galleons. 

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Seriously ???#thestudiobyfleur #dahlias #heaven

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Dahlias also have had a long presence in the garden, the small ones tucked between other perennials, the tall ones staked as sentinels in the border.

In our own time, when perennials and grasses have come to the fore, dahlias seemed to recede into the past, like lavender water, pedal cars and mahogany wardrobes. Now we have come to see that few other flowers are so luxuriant in their color, which includes shades of orange, red, burgundy and yellow. The darker the hue, the more intense it seems to be.

The cut-flower world, inherently photogenic and made for social media, has been given an enormous boost on photo-driven digital platforms in recent years. Nothing in October is as vivid as a bouquet of dahlias. Dahlias are back.

Serious hobbyists might have more than 200 plants in their gardens, growing in carefully prepared beds and supported by horizontally strung netting. It's more farming than gardening. 

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We haven’t had a frost yet, but robust armloads like this probably won’t happen again until next year. I’ll just echo many of the other flower farmers, I am sure going to miss these beauties but am quite looking forward to hibernation. Dahlias are still available, but not as abundant, and we’ll see what this cold front brings. #poppinblossoms #utahflowerfarm #utahflorist . . . . . . . . . . . . . . . . . . #utahgram #utahdiscovered #utahweddingflowers #utahweddingflorist #utahbride #utahvalleybride #utahbrideblog #bhgflowers #rsblooms #fromthegarden #americangrownflowers #fieldtovase #pinkflowers #dspink #countryliving #countrygarden #flowerfarm #seasonalfloweralliance #dahlias #dahliaseason #cafeaulait #inseasonblooms #inspiredbypetals #floristsandflowers #imsomartha #farmher

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If you grow five of one variety instead of one, the chances are good you will have a perfectly formed and pristine flower stem at show time. The rejects might be too slug-eaten or at the wrong stage of development. If the center of an otherwise immaculate dahlia is open - "blown" in grower parlance - you might as well stay home.

Gardening tip:

Leaves that are diseased and have dropped early because of excessive rainfall should be bagged and removed from the garden rather than added to compost or, worse, left in place. Good sanitation is key to reducing foliar maladies next year.