Garden Notes: Golden September

Golden yellows prevail this time of year.


Reds and russet prevail later on; the color of the present is golden. The light’s quality shifts to golden tints. Beautiful September days themselves seem golden; we sense their inherent ephemerality. Yellowed leaves scatter on dry soils under drought-stressed trees, excess jettisoned to reduce transpiration. Fields and lawns have turned golden and tan while awaiting late summer tropical depressions, as goldenrod in sloughs and roadside ditches blankets the ground in insect-riven golden coverlets.

In gardens too, gold flowering plants make a statement. Rudbeckia ‘Goldsturm’ has found a fitting place in innumerable sunny Island perennial beds, often beautifully paired with the lavender haze of perovskia. The clumps it forms are real punctuation points. Numerous other species and cultivars of rudbeckia, coreopsis, asclepias, members of the aster family, and late-blooming yellow daylilies demonstrate that ‘the yellows’ are pleasing and appropriate in late summer gardens.

September standout

Or do I mean standup? Pairing beautifully with “the yellows,” towering native vernonia is that eye-catcher to plant for a big bang at summer’s end. Several species, V. arkansana and V. noveboracensis (pictured), are especially useful in late summer gardens, and do well in moist to moderately dry Island soils. The common name is ironweed.

Vernonia’s glowing reddish-purple flowerheads reach two feet across, carried on stems that can reach six to seven feet tall in favorable locations. Infrequently found in garden centers, vernonia is among the plants in Polly Hill Arboretum’s online September sale. Visit to check out the sale.

Seed saving

We expend effort in the summer garden trying to keep plants from going to seed: deadheading and cutting back, all season long. By now, that cutting or snapping off seedheads in passing is automatic and ingrained.

Summer’s season is winding down. Golden September is the time of ripening, and if we have special favorites and things we want to save, we must unlearn our ingrained habits and let seedheads ripen. Luckily, seed saving is not a high-tech operation.

You might survey the plants and choose the color form, or the best example, for seeds to save. If harvesting from a flower, leave the seedhead maturing as long as possible, and cut it into an envelope or jar just before it shatters. If the seed is a favorite of birds, tie the seedhead in a Baggie.

If harvesting from a fruit, such as squash, cucumber, tomato, etc., let it also mature. Scrape the pulp away from the seeds, and place them in a sieve. Wash off pulp, and then spread to dry. Label and date, and place in mouseproof canisters. If you have room in a fridge, seed storage there is often recommended: cool, dark, and dry.

This season seems like a good time to start seed saving. Our supply lines appear subject to change: Some seed may become unavailable, or may increase in price.

Invaluable straw

When you see straw bales for sale, pick up a few. Straw is often unavailable when it is needed. Acquire bales of straw, not hay, when you see them, and store under cover for future use. I mulch potatoes with straw, and also cover seedbeds for garlic and shallots with it. Cover spot-seeded areas of lawn repair, or stuff into surrounds on tender plants and containers for winter insulation. In my experience, it has dozens of beneficial uses in gardens.


Aftercare for large-size tree installations in drought times includes watering for far longer — years — than you might think. They may yellow or lose leaves long after installation.

“Landscape size” specimens lose a large proportion of their roots when they are tree-spaded. The canopy is now larger than the root ball supporting it. The root-run of a mature tree when tree-spaded is more extensive than what the tree spade digs, and so the injured tree needs long-term nursing after it is settled into its new site.

Better still — use sapling-size trees wherever possible. They are more economical, establish better and faster, and with less watering. They often outgrow their landscape size fellows over the 10-year aftercare period.


In a huddle-by-phone, Lynne Irons and I discussed some flowering plants she had spotted and hoped to identify. I had pulled out the books that deal with ruderal and wild plants, and we came to a tentative identification: possibly Crepis tectorum (narrow-leaved hawk’s-beard), or more likely, Hieracium umbellatum (narrow-leaved hawkweed) or another similar, related Hieracium species.

Right there, by a perfect coincidence, one sees a great example of why common names are often impossibly confusing, hard to distinguish, and harder to recall correctly. Meanwhile, the botanical names are quite different from each other, and leave no room for confusion.

The references I checked: “Weeds of the Northern U.S. and Canada” (Royer and Dickinson); “Weeds of the Northeast” (Uva, Neal, and DiTomaso); and “Wild Urban Plants of the Northeast” (Del Tredici). These books were purchased either at Polly Hill Arboretum or the Garden in the Woods (Framingham) bookstores, but can probably be ordered online.

Or wild plants?

While all three books are guides to ‘weeds,’ I notice that just one of the three, Del Tredici’s, utilizes “Wild Urban Plants” in its title. Ralph Waldo Emerson famously quipped, “What is a weed? A plant whose Virtues have not yet been discovered.”

With the ongoing and implacable shift to suburbanization of formerly natural areas, and before they are irreplaceably gone, the plants beneath our feet deserve more knowledge and attention.

People know some of the names of common garden plants. However, when moving into the realm of the greenery that surrounds us, there is too usually a blank. Often, one hears any tall evergreen referred to as a “pine tree.” This is plant blindness.

Who will be left to identify and perhaps prize the mundane plant life surrounding us, if plant blindness is the way we trample through modern life?

Tick check every night!