Chrysanthemums are unequaled for their fall blooms and are the favorite fall flower in our area. They flower for three to eight weeks with blossoms that range from tiny buttons to immense globes of 8 inches.

Mums are rather unique in the flower world as they come in 13 different flower forms. These include the single and double flowers, pompom, spider, quill, spoon, incurved, reflex, brush, thistle, and others. Most of these types are not grown in the garden but are grown in greenhouses for exhibition. The size of the plants range from 18 inches to 6 feet. The word "chrysanthemum" is derived from the Greek words "chrysos" (gold) and "anthos" (flower). While the original plants bore only gold flowers, they now come in many colors, including yellow, white, pink, red, purple, lavender, orange, and bronze.

Mums are "short day" plants. Their blossoming period is triggered by the shortening days of late summer. It takes from six to 12 weeks for the flowers to open. Most garden mums grown in the home garden bloom in September and October. The types which require nine to 12 weeks to bloom are the ones raised in greenhouses and sold throughout the year.

Mums in bud and bloom for the home garden are available in stores and garden centers in early August. These are the types that normally begin blooming in September or early October.

The grower has induced the plants to bloom earlier by covering the plants with black cloth in late afternoon, beginning in midsummer. This provides the short days needed to trigger blooming. It also provides a longer blooming season for the gardener.

Plants that are purchased this summer in bud or bloom can be planted in the garden in sun or shade. They are easily transplanted because of their shallow root systems. Most of the September and October varieties are the cushion mums and are typically 18 to 24 inches in height. The flower forms are: single, double, anemone, decorative, spoon, and pompom. They should be planted in well-drained soil.

If the home gardener plans to keep his mums from year to year, they must be grown in full sun. If they bloomed in the shade, they should not be moved until new growth appears the following spring. The new growth appears in April. The plant can be lifted, and if desired, it can be divided into several sections. Most plants usually spread to 3 or 4 feet in width in several years and should be divided for maximum blooming.

Mums require plenty of space around them to develop properly. The roots require a soil that is loose and drains well after a heavy rain. A soil that is too soggy in summer or winter will adversely affect growth and survival. An ideal soil contains clay and compost.

They are very heavy feeders and should be fertilized in the spring with a 5-10-5 granular fertilizer and weekly thereafter with a 20-20-20 liquid fertilizer at half strength. No fertilization is needed after the buds are set. They must be kept moist and mulching is recommended. They will bloom at the same time each year, but this may be later than the year they were purchased because the grower may have forced them to bloom earlier.

For maximum flowering the plant must be pinched. This is the least understood technique of mum growing. It simply means cutting or breaking off the top inch of growth and forces the plant to produce side shoots.

The first pinch is made when the plant is 6 to 8 inches tall. Pinch or cut out the growth above the topmost leaves. Three new shoots are formed at the pinch; when these shoots are 6 inches tall, pinch them. A total of three pinches should be made with the last pinch made by July 15.

If you wish to have blooms by a certain date, start covering the plants each afternoon by 5 p.m. with a black cloth for six weeks. For example, if you wanted blooms by Aug. 1, start shading June 15. This will work for most hardy mums.

Pete Hale is a Master Gardener with the Penn State Master Gardener program.