The cartoon shades of red, yellow, blue, purple and nearly orange of primrose, Primula acaulis (or Primula vulgaris) are still partying strong. They do not seem to be aware that, although perennials that could regenerate next autumn, they are likely to be replaced with warm season annuals soon. The cute flat-topped trusses of half inch to inch and a half wide flowers are short, but stand up above the even shorter two to five inch long leaves.
All sorts of shades and combinations of yellow, orange, red, purple and blue, as well as white and monochromatic black can be found among the many varieties of pansy, Viola X wittrockiana. Pansy flowers are mostly about two inches wide, with a pair of overlapping upper petals, a pair of side petals and a single lower petal. Even though they stand only about half a foot high, flowers hover slightly above the foliage.
Here where winters are so mild, pansies get planted in autumn to bloom through winter, and then get replaced with warm season annuals in spring. They can survive through summer, but do not perform so well while weather is warm. Deadheading (removal of deteriorating flowers) promotes continual bloom. Related violas typically produce more profuse but smaller flowers, which are actually physiologically different.
Cool Season Annuals Eventually Replace Warm Season Annuals
Here in the mild climates on the west coast of California, the difficulty of getting new cool season annuals into the garden to bloom through autumn and winter is not selecting, procuring and installing the new annuals. It is the removal of the warm season annuals while they are still blooming and looking so good! Knowing that planting new annuals sooner than later will get them an earlier start is not always much consolation.
Pansy, viola, primrose, snapdragon and alyssum are probably the most familiar and favorite of cool season annuals, and are often allowed to bloom late into spring when they probably should be replaced by warm season annuals. Alyssum easily naturalizes, and can actually bloom all year in coastal or cool areas. Snapdragon are probably the most difficult of these favorites to grow, since they so often get infested with rust, a common fungal disease that proliferates where winters are mild.
Cornflower (bachelor’s button), stock, Iceland poppy, sweet William and calendula are probably a bit less popular only because they are not so conducive to mass planting as bedding plants. Cornflower and stock get taller than they should for beds, although they look great behind beds; and stock is excellently fragrant. Iceland poppy, sweet William and calendula do not often grow uniformly enough for large beds; and calendula does not offer much variety of color beyond shades of yellow and orange. Yet, all are great in mixed plantings.
Ornamental cabbage and kale are grown for their colorful foliage instead of flowers. Cabbage may be a bit more colorful; but kale can provide more variety of foliar texture. Because they form such bold rosettes of foliage that do not blend into each other like other bedding plants do, they are more often grown as narrow borders or in small mixed plantings instead of in broad uniform beds.
The ornamental potential of both Swiss chard and parsley should not be denied. Swiss chard has distinctively ruffled and glossy foliage that can be dark green or deep burgundy. Their prominent midribs and veins can be even more colorful with shades of greenish white, yellow, orange, red or pale purple. Parsley is rich green, with full, intricately textured foliage that happens to look quite sharp with white alyssum. The main problem with these two cool season vegetables is that their appearance can be compromised if they get eaten.
Autumn Annuals Transition From Summer
Cool season vegetables will replace warm season vegetables during autumn. Also, cool season annuals will replace warm season annuals. Neither simple task is easy for warm season plants that continue to perform too well to remove. Conversely, some finish early. Autumn annuals may compensate until cool season annuals become more seasonable.
Summers here are long, dry and somewhat warm. Even petunias and other annuals that enjoy warmth and tolerate aridity may not want to perform for so long. Without occasional grooming, they can get shabby by late summer. The recent unusually warm weather only accelerated the process for this year. Summer weather might continue into early autumn.
Consequently, it may still be a bit too early for some favorite cool season annuals that do not appreciate arid warmth. Pansies can get scrawny and lay low in response to warmth. Ornamental cabbage and kale is likely to bolt (general floral stalks) after exposure to too much warmth. Such annuals perform better or for a longer season after summer warmth.
This is why autumn annuals are so popular. They replace tired warm season annuals by the end of summer, and bloom until the weather is cool enough for cool season annuals. Autumn annuals generally bloom for shorter seasons than warm or cool season annuals, but most last until frost or significant rain. After bloom, a few are actually perennial plants.
Chrysanthemums and marigolds may be the most familiar of autumn annuals. Marigolds are actually warm season annuals that can perform just as well during spring or summer. Late installation allows late performance, which can continue until frost or sustained rain. Chrysanthemums are actually perennials, so can grow and bloom again for next autumn.
Celosia and alyssum, like marigold, are warm season annuals that perform late after late installation. Sweet William is a cool season annual that, after early installation, begins to perform earlier. Several types of aster naturally bloom late in summer or early in autumn. Even if nasturtium already succumbed to warmth, fresh seedlings may perform until frost. Old plants, prior to deterioration, could have provided seed, albeit feral, for their own replacement.
This is one of the more familiar of winter annuals. Yet, pansy, Viola X wittrockiana, is not just one species. It is a diverse group of hybrids of a few species, and includes viola and Johnny-jump-up. Generally, viola and Johnny-jump-up have smaller and simpler flowers. Pansy generates relatively larger and more colorful flowers, with more intricate patterns.
The most recognizable feature of popular pansy is the distinctive floral patterns that look like floral faces. Individual flowers may display a few distinct colors within such patterns. Alternatively, flowers may be a single color. The color range includes white, blue, purple, yellow, orange, rusty red and black. Big flowers can be as wide as two and a half inches.
Locally, pansy is a winter annual. The best bloom begins about now. If the coolest winter weather inhibits bloom, it is only temporary. Bloom is likely to resume before a lapse gets obvious. Although pansy is a summer annuals in other climates, it does not perform well in the locally arid climate during warm weather. Plants might get six inches tall and wide.
Winter Annuals Are Moving In
It is inevitable. It begins at about the same time that cool season vegetable plants start to replace warm season vegetable plants. Cool season vegetables are now in season, and will grow during autumn and winter. They replace warm season vegetables of spring and summer. Winter annuals, or cool season annuals, now do the same for summer annuals.
Some summer annuals, or warm season annuals, are already shabby by the end of their season. Their replacement is not so unpleasant. Those that continue to perform well into the end of summer or autumn are a bit more difficult to evict. No one likes to pull them up while they still bloom colorfully. Besides, new winter annuals may take a while to bloom.
Winter annuals, as well as summer annuals, require replacement because they live only for a single year. Some complete their respective life cycle within only a few months of a year. That is what their designation as ‘annual’ means. Several annuals have potential to survive as perennials, but are too unappealing to salvage through their dormant season.
Marigold and chrysanthemum are popular for autumn, but do not perform as well through winter. Cyclamen, which prefers a late start, is pleased to replace them by then. Although chrysanthemum and cyclamen are both perennials, few get the opportunity to perform as such. It is easier to simply remove and replace them with the next best seasonal annual.
Pansy, viola, Iceland poppy, sweet William, stock and various primrose are all in season now and through winter. Calendula and snapdragon are seasonable for autumn, and will be again for early spring. They survive and can even bloom through the middle of winter locally. Alyssum is technically a summer annual, but might bloom all through winter also.
Winter annuals are not as easy to grow from seed as summer annuals are. Because they grow during cooler weather, they grow slower. They therefore need to start growing early to be ready for planting now. It is perhaps more practical to plant most types as seedlings from cell packs. Cyclamen and ornamental cabbage commonly grow from four inch pots. These are innately more expensive than other winter annuals.
The advantage of cyclamen, Cyclamen persicum, is nonconformity. Bloom begins in autumn when there are not many other flowers to provide color, and continues until spring. Cyclamen then defoliate and go dormant through summer while most other plants enjoy the warm weather. Even their red, pink, white, purple or salmon flowers are inside out, with petals flared back. The flowers can stand as high as six inches, just above the somewhat rubbery foliage. The rounded leaves are mostly dark green with silvery or gray marbling
If used as annuals for one season, cyclamen are uniform enough for bedding. However, if later overplanted with warm season annuals and allowed to stay through summer dormancy, regeneration the following season is variable, with larger and smaller plants, and some that do not survive. As perennials, cyclamen therefore work best in mixed plantings, where variety is not a problem. Cyclamen should be planted with their tubers about halfway above the soil level, and should not be mulched. Soil should be rich and drain well.
Cool Season Annuals Are Cool
Now that it is time for cool season annuals, it is difficult to remove warm season annuals if they are still blooming and healthy. that is probably why so many of us prefer mixed plantings, where cool season annuals can be added as needed to replace warm season annuals as they deteriorate. Some warm season annuals that are actually perennials, like wax begonia and busy Lizzie (impatiens), can be cut back and overplanted with cool season annuals, so that some might regenerate next spring as the cool season annuals finish. Petunias may be looking overgrown and tired, but are at least easier to remove without guilt.
Pansies and smaller but closely related violas are probably the two most popular of cool season annuals. They work something like petunias, but for autumn and winter. They are commonly grown in uniform beds, but work just as well in mixed plantings. There are not many colors that can not be found in pansies, although only a few of the more popular varieties can be found at any particular nursery. Some are ‘solid’ colors. The most familiar varieties have those funny ‘faces’ that pansies are known for.
The various primroses require a bit more effort because deteriorating flowers need to be removed. They can also be a problem for the few who are allergic to them (like poison oak). Like the warm season annuals that can survive as perennials through winter, some primroses, particularly English primrose, can survive through summer as perennials. English primrose displays bright cartoon shades of almost any color. Fairy primrose are more commonly pastel shades.
Stock has an intense and distinctively rich fragrance. Taller types are excellent cut flowers, but are not so practical for uniform beds. Even shorter types are probably best in mixed plantings, or in borders with lower flowers in front. The single or double flowers can be white, pink, purple and almost red.
Ornamental cabbage and kale are grown for bold rosettes of colorful pink, white or pink and white foliage. The shades of pink range from soft light pink to rich purplish pink and almost red bright pink. Cabbage provides more color. Kale has more variety of foliar texture. Ironically, both look rather weedy, and should be removed as they begin to bloom in spring.
Chrysanthemum are strikingly colorful cool season flowers, but rarely bloom as uniformly as they do when first planted. Because they bloom so profusely, they need to be groomed frequently. If they get what they want, they can perform for several years, blooming all sorts of shades of yellow, orange, red, pink, purple and white. Chrysanthemum also displays a broad range of flower structures and sizes, from minute to jumbo.
Sweet William, Iceland poppy, calendula and alyssum are also in season. Yellow or orange calendula, with single or double flowers, is best through autumn, but may mildew by winter. Alyssum is white or subdued shades of pink or purple, and is actually good throughout the year, and can self sow indefinitely.
Whether feral or planted intentionally, nasturtium, Trapaeolum majus (which is actually a hybrid with two other species) is a delightful flower that just about everyone appreciates. Its eagerness to self sow and possibly naturalize in riparian situations attest to how easy it is to grow. Seed for many varieties is readily available. Feral plants provide feral seed.
Bloom of domestic nasturtium can be various shades, tints and hues of yellow, orange or red. Flowers can be striped or blotched with colors of the same range. Some are double. The palest yellow is almost creamy white. The darkest red is almost brown. Feral plants, after a few generations, generally revert to blooming with simple bright orange or yellow.
Plants are more or less annual, but can replace themselves almost as readily as they die out. Those that perform through spring and summer succumb to cooling autumn weather, as their (feral) seedlings begin to replace them for autumn and winter. Those that perform through winter may succumb to frost where winters get cool, but also self sow feral seed for next spring.
Chrysanthemum compensates for its lack of fragrance with rich color and variable form. Centuries of breeding have produced countless shades and tints within the yellow, orange and red range. This includes pink as a tint of red, cream as a tint of yellow, and bronze as a shade of orange. Some reds and pinks are precariously close to purple or lavender. There is, of course, white as well.
Flowers may be solitary big pom-poms, multiple small buttons, or anything in between. Many are daisy types, mostly with bright yellow centers. Spider chrysanthemums have strangely elongated and hooked ray florets, which are generally thought of as ‘petals’. Some chrysanthemums that would otherwise bloom with many small flowers can be groomed to bloom with fewer bigger flowers.
Chrysanthemums with compact growth and uniform bloom are popular as short term annuals for autumn. Their primary bloom phase is impressively profuse. Unfortunately, few get an opportunity to bloom again. Other cool season annuals replace most of them for winter. In ideal situation, with rich media and regular watering, chrysanthemums can actually perform as short term perennials.