What's in Season in Washington DC: Autumn

Autumn is the most underrated period in the Washington flower calendar. The region's growers produce material in September and October that is genuinely better than what they produce in spring, and almost nobody buys it because the associations attach to weddings and Easter rather than to the end of the year.

September: Dahlias

The dahlia season runs from late July through the first frost, and it peaks in September. For roughly six weeks the local supply carries a flower that is essentially unavailable in the imported trade because it does not ship.

Dahlias cover a range no other single genus manages — from small ball forms two inches across to dinner-plate varieties the size of a face, in every colour except true blue. The dark burgundy and the café-au-lait types in particular are what a great deal of contemporary wedding design is built on.

They last five to seven days, they hate being cold, and they need water changed frequently. Buy them fully open, because unlike most flowers dahlias do not continue opening once cut.

Alongside them: amaranth, celosia at its peak, zinnias continuing, and the first chrysanthemums, which are a considerably better flower than their supermarket reputation suggests when bought as a field crop.

October: Texture and the Antique Harvest

October shifts the palette from colour to texture, and it produces two things worth planning around.

Antique hydrangea is harvested from late August through October — heads left on the shrub to lignify and develop the mottled green, burgundy, bronze and dusty rose that cannot be produced any other way. This is the only window in the year for it, and heads bought now are usable for the following twelve months because they dry standing in a vase. Our Preserved Flower Dome is built from this material.

And seed heads, grasses and pods come into their own — nigella, scabiosa pods, poppy heads, ornamental grasses, bittersweet, rose hips. This is transparent, structural material that adds movement and depth rather than colour.

Foliage is also at its best. The Mid-Atlantic colour season runs through October, and branch material cut now carries colour that no flower supplies.

November: The Turn

The first frost in this region typically lands in early to mid November, and it ends the field season abruptly. Dahlias go overnight.

What remains is woody and dried: branches, berries, evergreens, seed heads, and whatever was cut and stored in October. Chrysanthemum continues from protected growing.

This is also when the imported supply takes over almost entirely, and it is worth being honest that anything soft and floral bought in late November came a long way.

Why Autumn Suits Buying Better

Three reasons that have nothing to do with fashion.

The material lasts longer. Cooler weather means less heat stress, slower bacterial growth in the vase, and flowers that were not fighting humidity in the field. An arrangement bought in October routinely outlasts the same arrangement bought in July.

It costs less. Autumn is not a peak gifting season, demand is lower, and the field crops are abundant right up to the frost.

And a great deal of it dries. Hydrangea, grasses, seed heads, amaranth and celosia all hold their form indefinitely, so an autumn arrangement can be allowed to dry in place rather than being thrown out — which is the only season where that is true as a general rule.

What to Buy in October Specifically

If you buy flowers once this autumn, buy antique hydrangea and buy more than you need. It is available for about eight weeks, it costs a fraction of what it will cost as a dried product in March, and it keeps.

Stand the heads in two or three inches of water and let them run dry over a fortnight rather than hanging them, which is the method that preserves the colour. Keep them out of direct sun afterward. Something in the tonal register of our Mixed Hydrangea will still be on the mantel next summer.

Buying Dahlias Well

Three things separate a good dahlia purchase from a disappointing one, and none are obvious.

Buy them fully open. Unlike almost every other flower, a dahlia does not continue opening after cutting — a tight bud stays a tight bud and then goes over. What you see is what you get.

Check the back of the head. Dahlias fail from behind, and browning or softness on the reverse means the flower is finished regardless of how the front looks.

And keep them out of the cold. Dahlias are frost-tender and chill-damage in a refrigerator, which is the opposite of the usual advice and the reason a supermarket dahlia is frequently poor.

For Thanksgiving

The seasonal material is the answer rather than anything imported. Branches, seed heads, grasses, chrysanthemum, dried hydrangea and foliage produce a table that belongs to the month, holds up across a long day in a warm dining room, and does not compete with the food — which is more than can be said for most of what gets sold for the occasion.

Low is the rule, as with any table people sit at, and unscented matters more than usual where a meal is the point.