Wax begonia, Begonia X semperflorens–cultorum, exemplifies simplicity. Its floral color is white, pink or red. Its foliage is green, bronze or dark bronze. Each floral color combines with each foliar color for a total of only nine combinations. That must be enough, though. Variants of these nine simple options, including some with fluffier double bloom, are rare.
Wax begonia is most familiar as a common warm season annual. However, it is probably at least as popular as a cool season annual. Actually though, it is a short term perennial. Except for during the coolest winter weather, established specimens may bloom all year. After minor frost damage, most regenerate efficiently. They need only minimal grooming.
Mature wax begonia should not grow any higher or wider than a foot. As bedding plants, they blend together. Individually, they develop densely ovoid form. Flowers are small but abundant. Foliage and stems are succulent, with a waxy sheen. New plants grow easily from cuttings or division. Wax begonia prefers rich medium and very consistent watering. A bit of partial shade should be no problem, but a bit too much can inhibit bloom.
Warm season annuals that started late last winter should be finishing their season soon. It might seem as if they replaced their predecessors, cool season annuals, only recently. This is the nature of annual bedding plants. They perform only for their particular season. It is now about time for cool season annuals, or winter annuals, to begin another season.
There is no need to hurry, though. The several different cool season annuals operate on different schedules. Only the earliest begin as small plants now, and even they can wait. Some prefer to begin later during autumn. Cyclamen and ornamental kale can even wait until winter. Only annuals that start as seed really must do so while the weather is warm.
Besides, some warm season annuals still perform too nicely for immediate replacement. Ideally, they are only beginning to deteriorate as they relinquish their space. Sometimes, some varieties are already grungy before their replacement. This facilitates their removal without guilt. However, some warm season annuals might continue to perform until frost.
Furthermore, some annuals, both cool season and warm season, are actually perennial. They merely function as annuals because their replacement is easier than their salvage. Busy Lizzie, for example, can remain mostly dormant through winter below new pansies. As the pansies finish in spring, the older busy Lizzie can regenerate for another season.
Sweet William and various primrose are cool season annuals that are actually perennial. Both can bloom until next spring becomes too warm for them. Then, they become mostly dormant until the following autumn. Any that remained dormant through last summer can regenerate and bloom this autumn. Perhaps they take turns performing with busy Lizzie.
Pansy and viola are the most familiar and reliable of cool season annuals. Marigold and snapdragon are popular now, but only as autumn annuals. They may not perform well for winter. Wax begonias might perform almost throughout the year with grooming after frost. Stock is the most fragrant of the cool season annuals. A few short varieties are available.
Pincushion blooms in pastel blue, lavender pink or white.
The oddly protruding stamens of pincushion flower, Scabiosa columbaria, are ideal for bees collecting pollen. To us, they resemble pins stuck into the somewhat flat surface of the composite (daisy like) flowers. To bees, they are a flea market (or bee market) of pollen. Bees easily stroll the two inch wide flowers to peruse the merchandise on display.
The pale lavender, blue, pink or white flowers on limber stems are good cut flowers. The grayish foliage is deeply lobed and nicely textured. Mature plants can be two feet tall and broad. Bloom begins by summer and continued until frost if fading flowers get plucked. Although perennial in mild climates, pincushion flower is more often grown as an annual.
Cool season annuals that started late last summer should be finishing soon. A few might have potential to continue as perennials. However, about as many are done or decaying. Now, warm season annuals, or summer annuals, should eventually start to replace them. If it seems early, it typically does for such bedding plants before their respective seasons.
Some annuals can not decide if they are cool season annuals or warm season annuals. Stock is actually a cool season annual but becomes more popular now for spring bloom. Wax begonias might have survived through winter to resume growth for another season. Primrose is a cool season annual that rarely gets too warm locally to continue blooming.
These indecisive annuals can actually be an asset to home gardens. Stock, for example, can replace old pansies while it is still too early for petunias. It compensates for cool and warm season annuals with more definite seasons. Petunias will be ready before stock is done. Some garden enthusiasts replace seasonal annuals for each of their four seasons.
Warm season annuals, like all annuals, are contrary to sustainability. Although many can perform as perennials, few actually do. Those that truly are annuals complete their entire life cycles within one year. Their main purpose is to provide floral or perhaps foliar color. Texture and form are also assets. Annuals are popular because they serve this purpose.
The most popular of warm season annuals grow from cell packs. Those that start earliest are already available, including wax begonia and lobelia. Petunia, impatien and annuals that crave more warmth will become available later. Four inch potted annuals are bigger than those in cell packs, but more expensive. They are even more expensive in quantity.
Many more varieties of warm season annuals are available as seed. Countless more are available online than from nurseries. However, seed requires more effort. Most must start early. Although most grow well in flats or cells, some prefer direct sowing. Sunflower and nasturtium are very vulnerable to the distress of transplanting. Seed is the logical option. Many seed are less expensive than six cell pack seedlings.
Because winters here are so mild, Iceland poppy, Papaver nudicaule, gets planted out in the garden in autumn to bloom through winter and into early spring. Where winters are cold, bloom must wait until after winter, whether plants are put out in autumn or sown from seed as winter ends. Iceland poppy prefers good drainage because it is out in the garden during the coldest and rainiest time of year, but is otherwise not too demanding. Picking the flowers and removal of deteriorating flowers (deadheading) promote continual bloom.
Circular flowers up to three inches wide in shades of orange, yellow, pink, white and nearly red hover up to a foot high on wiry and hairy stems. Prominent fuzzy stamens are bright yellow at the center of each flower. Some varieties have brighter colors and taller stems. The hairy and deeply lobed leaves form basal rosettes about five inches wide.
From spring until autumn, semperflorens begonia, which is also known as fibrous, bedding or wax, begonia, is a warm season annual. They actually start to deteriorate as the weather gets cool this time of year. However, they do not necessarily need to be pulled out as their season ends. In sheltered locations or with protection from frost, they actually survive through winter as perennials. They are so easy to propagate by cuttings or division of overgrown plants that tired older plants can replace themselves with their own babies before they get too ugly.
The small flowers of semperflorens begonia can be white, red, or various shades of pink in between. Foliage is more often green or bronze, but can be reddish or variegated. The largest plants get only a foot tall. Denser dwarf types are half as tall. Semperflorens begonia likes rich soil and regular watering (when it is not raining). They prefer partial shade, but will take full sun if mixed with other plants that keep things cool and humid.
Because they do not like warm weather through summer much, sweet William, Dianthus barbatus, is appreciated more as a cool season annual from autumn into winter and even into spring. They can also be planted early in spring for color before summer warmth. They can sometimes survive as perennials in sheltered areas, particularly if mixed and hidden amongst other perennials and annuals. Deadheading (removal of deteriorating flowers) prolongs bloom.
New plants are easy to propagate from division, cuttings or layering of tired older plants. (Layering involves rooting prostrate stems by burying them slightly and them separating them when they have developed roots.) By the time the old plants become too deteriorated to salvage, the new cuttings or layers should be ready to replace them. New plants like to start out in rich and well drained soil, but not watered too much since they can be susceptible to rust and fusarium wilt.
The white, pink, rosy pink, red, somewhat purplish or bicolored half inch wide flowers form rather flat dense trusses on top of short stems. Minute but abundant green bracts fill the spaces between the individual flowers. The rich green leaves below are about an inch to two and a half inches long. Mature plants of the more common varieties are typically less than a foot tall and wide. More compact and larger varieties are available as seed.
The longer and cooler nights of autumn will soon finish the season for zinnias. (Most, but not all of the common zinnias are of the species Zinnia elegans.) They are really at their best while the weather is warm through summer and the beginning of autumn. As the garden warms up at the end of next spring, new seedlings can be planted, or zinnia seed can be sown. They like rich soil and regular watering, but are susceptible to mildew in humid spots. Sunny areas with good air circulation are best.
Like related chrysanthemums, zinnias are quite variable. Although the simpler forms remain more popular; double, cactus flowered and crested forms are also available. Flowers can be less than an inch wide to more than five inches wide. Their color range includes white, yellow, orange, salmon, pink, red, rose, purple, lavender and even green. The narrowly oval leaves can get to about four inches long. Compact types stay about a foot tall and wide. Large types get twice as wide and more than three times as tall.
Calendula dislikes summer warmth and may not last completely through winter, but should last as long as marigold.
What was probably the last of the warm weather for the year really got the zinnias going again; but only for their leaves to become dusted with powdery mildew in the subsequent long cool nights. No matter how good the zinnia flowers still look, it is time for cool season annuals.
In mixed plantings, cool season annuals can be ‘plugged’ (as seedlings or small plants) or sown (as seed) among the warm season annuals so that they are ready to perform as the warm season annuals succumb to cooler weather. Of course in more uniform beds, warm season annuals will eventually need to be removed to make space for their cool season replacements.
Pansies and related violas are likely the two most popular cool season annuals. They fill in nicely as bedding plants or are nice components to mixed plantings. They perform best early in the season while the weather is still a bit warm, but should last until the weather gets too warm the following spring.
Primroses and Iceland poppies can take a bit more effort since they need ‘deadheading’ (removal of deteriorating flowers) to continue blooming. Primrose can also be hazardous to anyone who happens to be allergic to them, causing skin irritation comparable to that of poison oak! Some primroses are very brightly colored, while others are more subdued and elegant shades of pink and white. Iceland poppies are mostly pale shades of orange, yellow, pink and white on wiry stems.
Chrysanthemums, which are actually perennials, are the most variable of the cool season annuals, with a wild range of colors and flower forms. The varieties most popularly grown as annuals stay low and compact. Taller types make good cut flowers, but are not so practical for bedding. The related African daisies, which are incidentally similar to the ground cover of the same name, lack the variety of flower color and form, but are easier to grow; particularly as a perennial long after other cool season annuals are gone.
Calendulas are another simpler chrysanthemum relative that are more proportionate to typical annuals, since they get only a few inched deep. They would probably be more popular than they are if they provided more colors than their marigold like orange and yellow. Unlike chrysanthemums and African daisies, calendulas really are annuals, so do not last long into warm weather.
Red, white, pink and rosy pink flowers among rich green foliage can be provided by sweet William (dianthus). They not only tolerate a bit more shade than some other cool season annuals, but are also likely to survive sporadically as perennials where protected from warm exposure through spring and summer.
Stock is the best cool season annual for fragrance. It smells like carnations, but much stronger. Short varieties are good bedding annuals, and even better for mixed plantings. Taller varieties are great cut flowers.
French marigold is one of the most popular annuals of autumn. Pot marigold, Calendula officinalis, provides similar color with daisy like flowers. Most are bright orange or yellow. They lack only the warm burnished red of French marigold. They compensate with more variety of their pastel ranges. Their single or double blooms are two to three inches wide.
Within cooler climates, pot marigold blooms between spring and late autumn frost. Here, it blooms better through mild winters, with only minor pauses for any mild frost. It is more likely to dislike summer warmth. Like many seasonal annuals, it can technically grow as a short term perennial. However, also like others, it performs best for a particular season.
During their season, taller varieties may grow a bit higher than two feet. Most are shorter. Their oblong and slightly fuzzy leaves are mostly between two to five inches long. Some develop wavy margins. Mildew is sometimes a problem. Deadheading promotes bloom. However, a few deteriorating flowers can remain to provide seed for another generation. Subsequent generations eventually revert to simple and single yellow or orange bloom.
Tony Tomeo 