Tramping through a collage of browned and yellowed tulip poplar leaves on my way to the front door today I realized I have absolutely no desire or plans to sweep them up. They symbolize the end of a busy season and a beautifully gentle month ahead, and contribute to the earthy fragrance I’m starting to pick up in the early mornings and early evenings.
The enchanting month of September pulls us back into the garden after the heat of August elbowed us out. It’s a fantastic month of the year to be gardening in Virginia. Our first frost date is in mid-October, and while there are many plants beginning to react to noticeably shorter and somewhat cooler days, so many plants in my garden are only just coming into their own. Blossoming thunbergia, ipomoea and clitoria vines, ‘David Howard’ and Happy Single® and Mystic® series dahlias on fire. Grasses such as panicum, calamagrostis and miscanthus sending up long frothy stems, and all of the panicle hydrangeas that I grow in full flower or beginning to russet.
This September is particularly delicious as I will be home for most of it, having set aside the month (and schedule) to travel abroad, and then deciding what I really needed was time to play and work at home. This is my chance to tweak the garden, make plans for next year and catch up on writing projects.
At the end of the month I have been fortunate enough to be invited to Better Homes and Gardens’ BHG Stylemaker Event in NYC celebrating 100 years of this iconic American magazine. I’m looking forward to seeing editors and friends in person in this vibrant city –especially as it will give me an opportunity to walk The High Line in its full autumn splendor and perhaps sneak up to the new floating garden Little Island off the upper west side of Manhattan in Hudson Park.
Meanwhile, a short, precious month needs to be made the most of. September gives us a chance to miss the summer before it’s gone — an opportunity to come back to our gardens and reconnect before they melt away into true autumn.
“I should have planted that!” for the September garden
Carefully observing neighboring gardens month-to-month allows you to successfully increase your garden’s display season without having to experiment too much with regional timing. Make a note of the plants you love and keep it with you when you go plant shopping during the next planting season.
For the cooler month of September in the Mid-Atlantic, let me introduce you to a fantastically versatile grass and its fat, gorgeous flowers – Korean feather reed grass (Calamagrostis brachytricha) Zone 4-9
This plant is a perfect example of why we need to regularly visit gardens, neighborhoods and public spaces in our own regions to see what might fill a gap in our own gardens at a certain time of year.
While everyone and their mother is growing Calamagrostis x acutiflora ‘Karl Foerster’ (and quite rightly too!), C. brachytricha is a grass I was introduced to by seeing it grown at Chanticleer in Wayne, PA several years ago – at the peak of its flowering. The large feathery plumes with subtle violet undertones caught the strong afternoon light, softened it, and sent it out again.
I’m always on the lookout for great grasses, and this was one. I picked up a plant that fall, and eventually divided it to replace some sloppy, underperforming Pennisetum orientale ‘Karley Rose’ along the pergola.
And that’s this grass’ strength – it can cope with a partial shade position without displaying what can only be called ‘bed head.’ This area of the garden gets 5-6 hours of sun, and many full sun grasses struggle and flop in that situation.
I do lightly stake/tie up C. brachytricha upon flowering, just to ensure that those fat feathery panicles don’t hit the ground after a prolonged rainstorm, but for the most of the season it’s quite good on its own – the ½ inch wide leaves are medium green and glossy, unless disfigured by rust.
How to Grow Calamagrostis brachytricha
Full sun to partial sun. Suitable for a range of soils, but happiest if soils are on the moist/average rather than dry/average. For me this means that it has good years and bad years, as I have it in a drier area and its display (and susceptibility to rust), is dependent on that year’s rainfall. Cut this grass back in late winter and divide (if desired) in spring. C. brachytricha will self-seed if conditions are good, but is easily pulled. Hasn’t been an issue in my garden as (I suppose) conditions are not ideal. Don’t forget to cut a few flowers for flower arrangements, as it holds up well in a vase.
Outside Tasks in September:
♦The fall garden is here, whether you prepared for it or not. If you have good sized kale or collard seedlings, you should be able to get away with one more planting, but forget about a last sowing of green beans. Garlic should be planted soon for an early summer harvest and you should be able to squeeze in a sowing of leaf lettuce at the beginning of the month.
♦If you have a cold frame, planting lettuce seeds throughout the month can give you a respectable crop of winter greens. Look out for an old duvet or comforter at thrift stores for insulating your frame on cold nights.
♦Bulbs, bulbs, bulbs. At this time of year you can get a respectably-sized daffodil or allium from large chains and independent nurseries, but if you are looking for a specialty daff, you’ll need to get that order in very very quickly. Like yesterday.
♦Great month of the year to build. A shed, a coop, a deck, a fence, a pavilion (as mentioned above). After the winter has had a good go at beating the heck out of pressure treated wood with wind and rain, you’ll be able to stain it in the spring. Always give treated wood at least six months before staining.
♦Time to move those plants you have wanted to move since July. If you want to move zone-marginal plants, trees, and shrubs, (those that are only just hardy in your zone), it’s a good idea to put this off until early spring.
♦If you have a lawn and wish to feed it, now is the time to do so. Re-seeding or sowing a new lawn is also a good job for cooler September days.
♦Test your soil pH and amend your soil as necessary to give the winter a chance to temper additions of lime or sulfur. This is not a job you want to do in the spring – plants can suffer from soil that’s had its pH recently amended.
♦Good time to amend the organic content of your soil with compost or manure, but avoid putting actual fertilizer (organic or non) on your soil till spring. The active ingredients will only leach out over the winter, particularly the nitrogen.
♦Are you a forager? With its kiss of cooler weather and an uptick in moisture levels, September begins the fall mushrooming season. I routinely find wood ears and oyster mushrooms at this time of year. Black trumpets and chanterelles still elude me. If you want to learn more about the history and lore of mushrooming, and get an ID handle on the ‘foolproof four,’ may I suggest Chanterelle Dreams, Amanita Nightmares, by Greg Marley.
Inside Tasks for September:
♦The earlier you can start thinking about your winter refugees (those plants that must be protected indoors) the better. Houseplants that you wish to display should come in earlier rather than later (ficus, schefflera, citrus) to minimize leaf loss.
Start to get an indoor seating arrangement in mind, so all is not chaos at the end of the month, and check and treat plants now for insects like scale and mealy bug to treat BEFORE they come in.
♦If you are potting up smaller plants, rooted cuttings etc… into larger pots for the winter, that plant needs as much time as possible to adjust to a larger pot and put some roots out. Make sure that unplanted pots are kept in a sheltered location with access to natural rainfall.
♦Don’t forget to gather unusual seed heads and dried flowers from your garden for inside decorations over the winter. If you let summer hydrangea heads go late into October, mildew will be the overwhelming theme of all bouquets.
“By all these lovely tokens
September days are here,
With summer’s best of weather,
And autumn’s best of cheer.”
– Helen Hunt Jackson
– from “September”