Chrysanthemums are the showstoppers of the autumn garden. Each flower consists of ray florets in a rainbow of colors including white, yellow, green, bronze, orange, red, pink, purple, and countless bicolors. They are classified into a dozen groups according to flower form. The aromatic foliage, oval to lance-shaped and 2" to 7" in length, may be shallowly or deeply lobed or even feathery.
The Chrysanthemum is one of the longest cultivated of ornamental plants, having been grown and hybridized in China for over 2500 years. The name derives from the Greek, chrysos (gold) and anthos (flower), likely referring to the yellow Chrysanthemum coronarium. The genus consists of about 20 species of bushy, upright annuals and herbaceous perennials, some with woody bases.
Originating in the Mediterranean region, annual species typically grow in dry fields and wasteland. Herbaceous perennial species originate from the Arctic, Japan, China, and northern and central parts of Russia.
Chrysanthemums are usually talked about in two groups Hardy Garden mums and Exhibition mums.
Hardy Garden mums
The most popular chrysanthemums are the ones known as garden mums. These robust beauties bring color to the late summer/fall garden when it needs it most. Garden mums are low maintenance, care free, inexpensive, instant fillers in a range of vibrant colors. Although often sold mostly (or exclusively) in fall, they are perfectly perennial in our area and will perform steadfastly for you year after year.
These are divided into 13 different styles by the National Chrysanthemum Society. These types are the kinds you see at florist shops. They come in beautiful colors, and sizes that are truly exhibition worthy. They can be grown in a garden situation but often require more attention and cold protection that the Garden types. It is uncommon for us to have them for sale as we do not have a consistent supplier. If you are interested in finding Exhibition mums we suggest you contact the Oregon chapter of the Chrysanthemum Society at Portland@mums.org for information.
Read more about the 13 styles in this article at the National Chrysanthemum Society Website.
Common Name: Mum
Origin: Mediterranean region
Culture: Grown primarily for their showy flowers which can measure up to 12 inches across,
Maintenance: Chrysanthemums will grow in most any soil type. However, amending the soil with compost, manure, or peat moss is very beneficial. Planting with an organic starter fertilizer and a little gypsum or lime is also recommended.
Plants should be placed at the same level in the soil as in their original container, never deeper. Good drainage and air circulation are critical for disease prevention. At least four hours of direct sun is required, though more is preferred.
To keep plants bushy and floriferous regular and timely pruning is recommended. If plants are more than 10" tall by July first cut back to 6", always leaving some foliage below the cut. This encourages shorter, more compact plants at bloom time. When growth resumes, pinching out the very tip of each stem will promote further branching and flower production.
Small-flowered, late blooming types can be pinched up to August 15th. Large-flowered types should not be pinched after July 15th.
The regular use of high-nitrogen and potassium fertilizer, such as 10-10-2 will vastly increase both flower size and numbers. Top dressing with a slow acting fertilizer at planting time, followed by weekly application of a liquid fertilizer works well. After August first switch to a low- or no-nitrogen fertilizer to limit new growth. This will help the plants put energy into flower development rather than foliage.
Pests and Diseases: Commonly attacked by aphids, earwigs, leaf miners, spider mites, and white flies. Careful monitoring of insect populations and early intervention can prevent infestation.
Plants are also prone to fungal rot, gray mold (Botrytis), powdery mildew, and white rust. General garden cleanliness, proper spacing of plants to ensure good air circulation, and watering at the base of the plant rather than the foliage all will help mitigate disease issues.