How many late season flowers are there? We gardeners are always happy in the spring when our first snowdrops or daffodils open their blossoms. The year of bloom has begun! Many of us wonder how long we can keep the garden blooming through September and October. I have found there are many possibilities.
Zinnias are an amazing annual blooming through the fall season. They come in many forms from singles, with just one row of petals, then semi-double with two rows of petals with a visible center. I think the beautiful Profusion zinnias fall into that class. These zinnias give bees a good landing space as they fly in to collect pollen and honey. There is also the double flowered zinnia where the center is not visible, and the cactus variety with petals that curl toward the underside.
Butterflies and bees love all zinnias. Zinnias will bloom until hard frost, providing pollen and honey for bees and other insects as well as butterflies for a long period. They also provide a long season of bouquets for the gardener.
Helenium autumnale, also known as sneezeweed, is a perennial and late season flower. I have a clump of sunny yellow helenium which should bloom well into October. There are many varieties like bright yellow Mariachi, red and yellow Mardi Gras, and deep red Salsa. Helenium likes full sun, and happily for me it also likes rich damp soils. I can provide good compost, and our garden site is definitely classed as damp.
Sheffield daisies are members of the chrysanthemum family. They have pink petals around a golden center. They bloom until hard frost. Sheffies are about 18-24 inches high, but they are languid and tend to sprawl. They are vigorous, need full sun, tolerate drought, and bring absolute delight. I love my sheffies. And so do the butterflies. These are the latest bloomers in my garden.
Boltonia is the opposite of the languid sheffies. Boltonia, also known as false aster, has small daisy-like white petals around a yellow center. One of its great advantages is that this five foot plant is very sturdy and does not blow over easily. It needs full sun. If its location is too shady or the soil is too rich and damp, it will get a little floppy.
Asters will bloom well into October. Tall lavender aster Frikartii and rosy Alma Potchke are two familiar asters that will grow about three feet tall. Stokes aster Peachie’s Pick has a blossom like a large blue cornflower on shorter strong stems. It likes sun, but not damp or dense soil.
If you have a good sunny spot physostogia, otherwise known as obedient plant, will continue blooming well into October. Obedient plant has spikes of flowers in pink or white that can reach two feet tall.
All of these perennials (and others) benefit from being pinched back in early June. Pinching off a main stem early in t he season will encourage the plant to make new stems. Plants will have a fuller shape and more flowers.
Very different kinds of late bloomer are the sedums. Autumn Joy with its ever-darkening red velvet flower heads started the trend some years ago. Autumn Joy is just under two feet tall, with nearly as wide a spread. Nowadays there are many more varieties including the 18 inch purple-pink Neon, 12 inch pink Crystal Pink, and tall 30 inch Thunderhead with deep rose red flowers and dark foliage.
There are other ways of putting color in the autumnal garden. I have a red winterberry and a golden winterberry that are just brilliant under the sunny skies of autumn. They don’t need full sun, but these swamp plants do like a damp or wet spot.
In the sunniest parts of my garden I still have coreopsis, turtlehead, black eyed susans, and a deep red yarrow still blooming. I treasure every one.
We cheer our spring crocus blossoms, but some of us cheer on our autumn crocuses. American Meadows and Brent and Becky Bulbs are two companies that sell autumn blooming crocus and colchicum. These have to be planted in the summer. There have been many autumns when I suddenly look at my fall garden and realize that once again I gave it no thought in the summer. No mid-summer thought, no autumn crocus. Again. However, I did finally plant several autumn crocus bulbs in my Heath garden.
Once you have planted autumn crocus bulbs in early August, you will never have to give them another thought. The autumn crocus produces foliage during the summer, and then disappears. I was always shocked when I walked out to the border next to my house in Heath and saw large crocuses thrusting their heads through my poorly weeded garden. I had forgotten all about them. Year after year.
I have put a marker on my new 2020 calendar from the Umass Extension Service. This beautiful and helpful calendar gives daily gardening tips and leaves room for my own notes like “Order autumn crocus bulbs on July 15.” The cost of the calendar is $14 and there is free shipping if you order before November 1. Log on to http://ag.umass.edu/landscape/publications-resources/umass-extensions-garden-calendar and give yourself an early Christmas present.###