Bedding Dahlia

Bedding dahlias can perform as perennials.

Dahlias are as variable as related chrysanthemums. Rare tree dahlias can grow ten feet tall from the ground annually. Most popular dahlias grow less than half as high with more lavish bloom. Bedding dahlias are less than a foot and a half tall with smaller but profuse flowers. They are popular as warm season annuals, but can be perennial like the others.

Bedding dahlias are neither as ornate nor as diverse as those that are better cut flowers. They compensate with foliar density and floral profusion. Their flowers are less than five inches wide, and could be about half as wide. Their floral color range is limited to yellow, orange, red, pink and white. Floral variegation can add another color of the same range.

Bloom continues through summer and autumn, until frost. Deadheading promotes better bloom. Dormant tubers may remain in their gardens through winters here. They could rot, though, while their soil remains cool and damp. If dug and stored for winter, they prefer to return to their gardens prior to spring warmth. Dormant tubers propagate well by division.

Perennial Annuals

New Guinea impatiens (with ivy geranium) from last year.

Annuals complete their entire lifespans within a single year.

Perennials survive for more than a single year.

Biennials grow vegetatively during their first year, and then bloom, disperse seed and die during their second year, but that is another story.

Most species that are appreciated as annuals here actually have potential to be perennials, even if only short term perennials. They are only replaced annually because it is easier than maintaining them through their dormant season.

For example, busy Lizzy is a warm season annual that gets installed for spring and replaced with cool season annuals for autumn. However, if cut back and sheltered from frost, it can survive through winter to perform for the following spring and summer. Actually, it can survive perennially like this for quite a few years, and as it ultimately deteriorates, it can replace itself with its own cuttings or layered stems.

Brent did this with New Guinea impatiens from last year. He neglected to replace them for winter (which is quite brief there), and then noticed that they resumed growth as winter ended. Now, they are huge and even more spectacularly florific than they were last summer.

The picture above shows where I camp out in his backyard when I go to Southern California. Most of the white bloom to the right is actually ivy geranium that cascades below the New Guinea impatiens, but most of the white bloom to the left is New Guinea impatiens above ivy geranium. (White on white was not quite as monotonous when each of the two species maintained its distinct form last year.)

Small terrace at the western margin of the garden.

This other pair of potted dwarf Alberta spruce surrounded with the same New Guinea impatiens above, with a close up below, flanks the steps to a small terrace at far western margin of the garden.

These New Guinea impatiens are huge because they resumed growth from last year.

New Guinea Impatiens

New Guinea impatiens can be perennial.

Busy Lizzie had been unavailable for years because of a downy mildew epidemic. It has only recently been regaining availability and popularity. During its absence, New Guinea impatiens, Impatiens hawkeri, became more popular. Although a closely related species of the same genus, the two are actually very different. Resistance to mildew is important.

Besides that, New Guinea impatien is about as foliar as it is floral. Its bolder and slightly bigger flowers are notably less abundant than those of busy LIzzie. Also, its floral color range is limited to white, pink, red, lavender, magenta or orange. Its rich green or bronze foliage below compensates though. Many cultivars are variegated with yellow or salmon.

New Guinea impatiens are unfortunately a bit more expensive than most other annuals. The smallest that are available are in four-inch pots. They are unavailable in smaller and less expensive cell packs. They can grow about a foot wide and slightly taller if crowded. During winter, they deteriorate; but they can be tender perennials with shelter from frost.

Annuals Change With The Seasons

Several perennials are useful as annuals.

Winter continues. It will not end until March 19. Wintry weather is unconcerned with such dates though. It could end at any time, or continue a bit later. Vegetation is more aware of this than we are. It wants to be ready regardless. Cool season annuals linger as long as they can. As they no longer can, warm season annuals should be ready to replace them.

Warm season annuals, or summer annuals, include both bedding plants and vegetables. They perform seasonally as cool season annuals do, but through warm seasons instead. They perform for only one annual cycle, although several have potential to be perennial. Removal of perennials is necessary only because subsequent annuals need the space.

All sorts of annuals are available in cell packs from nurseries. They become available as they become seasonable. Those that bloom for late winter and early spring are available now. More of those that bloom best during warm weather should become available soon. It is still a bit too cool and early for most of them. It is not too early for their seed, however.

Although plugging cell pack seedlings into a garden is easier, some prefer to sow seed. Those who do so should begin about now so that the new seedlings are ready by spring. Many seedlings require the warmth and shelter of a greenhouse to grow. As they mature, and the weather warms, they relocate into their garden. Other seed prefer direct sowing.

Many more varieties of annuals are available as seed than as seedlings from nurseries. Even if only a few varieties of seed are in nurseries, countless more are available online. Also, some flowers from previous seasons provide viable seed for subsequent seasons. There are a few reasons to justify the extra effort of growing annual seedlings from seed.

Sunflower and nasturtium are among the warm season annuals that prefer direct sowing. Their roots dislike confinement within cell packs. They recover slowly from transplanting. Cosmos and alyssum do not mind transplanting, but also grow easily from direct sowing. Seed for many varieties can start now because the weather will be warmer as they grow. Petunia, impatien, zinnia and lobelia are easier from cell packs later.

Perennial Annual Dahlias

Annual dahlias are expected to be, as their designation implies, annual. In other words, they grow in the spring, perhaps from seed, bloom through summer, and then succumb to frost during their first winter. Some are likely grown from cuttings or division of nursery stock tubers, in order to be ready for spring earlier than seedlings. Regardless, they are not expected to survive for more than one year.

Most other dahlias are expected to be perennial. That is how their expense is justified. Most are sold while they are merely dormant tubers, and are generally more expensive than annual dahlias. Some, especially the trendy sorts, are significantly more expensive.

‘Cafe au Lait’ was a trendy dahlia a few years ago, and is still trendy. We procured one at work. It performed somewhat well for the first season, and was then dug and stored for winter. It did not perform well for the second season, and was then dug and stored again, but did not survive through winter.

Four smaller annual dahlias were procured in conjunction with the single ‘Cafe au Lait’ dahlia. They were relatively inexpensive, but delightfully colorful. They bloomed nicely around the larger ‘Cafe au Lait’ dahlia. They were also dug and stored for winter after their first season, although we knew that we should likely merely discard them. One had actually divided into two. These annual dahlias bloomed better than ‘Cafe au Lait’ for their second season, and then again, were dug and stored for winter. Unfortunately, three, including one that divided during the previous winter, did not grow for long after last spring. However, two of the original four annual dahlias continue to bloom, and will be dug and stored as they succumb to frost this winter. These annuals have been more perennial than the perennials.

Wax Begonia

Wax begonia is potentially a perennial.

Simplicity is a recurring theme among wax begonia, Begonia X semperflorenscultorum. Floral color is white, pink or red. Foliar color is green, bronze or dark bronze. Each floral color combines with each foliar color. Variation within this simple color range is minimal. So is variation of foliar or floral form. Cultivars with slightly fluffier double bloom are rare.

Perfection eliminated the potential for improvement. Regardless of such simple variation, wax begonia is among the most popular annuals. Technically, it is perennial. Technically, it prefers warm weather. It remains available as cool season color after summer because it blooms until frost. Later, it can recover from minor frost. Without frost, it blooms all year.

Mature wax begonia rarely grows higher or wider than a foot, with densely rounded form. Flowers are small but abundant. Both leaves and stems are succulent and tender, with a waxy sheen. Propagation is remarkably easy by cuttings or division. Consistent watering is very important. Partial shade is tolerable, but if too shady, can inhibit bloom somewhat.

Sweet Alyssum

Sweet alyssum has potential to naturalize.

My neighbor describes sweet alyssum, Lobularia maritima, as a ‘polite’ weed. It naturalized over an area of her vegetable garden that was not in use at the time, but was easy to get rid of when the space was needed for something else. A few plants that were left in the perimeter bloom almost continuously and fill in other unused space between herbs and perennials without interfering with them.

As a bedding planting, sweet alyssum is most often planted from cell packs like most other annuals. Yet, seed is so easy to sow in bare spots among mixed annuals or perennials. Naturalized sweet alysssum sows seed so abundantly that new plants replace old plants before the old plants deteriorate.

Bloom is most often white, but can be shades of pink or purple. However, naturalized sweet alyssum eventually reverts to classic white. The minute, sweetly fragrant flowers form small, round clusters over the delicate mounds of finely textured and sometimes sparse foliage. The tiny leaves are only about an inch long and quite narrow. The largest naturalized plants are not often more than a foot tall.

Primrose

These sorts of primrose almost seem to be synthetic because of their bright but simple color.

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.

Oxeye Daisy

Oxeye daisy is actually a perennial.

Like several annual warm season bedding plants, oxeye daisy, Leucanthemum vulgare, is actually perennial. Also, some of the less extensively bred sorts disperse enough seed to naturalize and potentially become invasive. Increasingly popular modern varieties that are prudent with seed might not be true to type. Some might revert to more prolific forms.

Modern varieties should not get much higher than a foot and a half. They should also be more dense than the simple species, which gets a few feet tall. Foliage and form is quite variable among varieties. Stems are solitary or branched. They may be leafy or sparsely foliated above basal rosettes. Leaves might be lobed or serrate, with or without petioles.

The solitary, paired or tripled composite blooms of oxeye daisy are not so variable. They are classic daisies, with a dozen to three dozen clear white ray florets surrounding bright yellow disc florets. Without deadheading, fresh new bloom overwhelms deteriorating old bloom. Oxeye daisy is splendid as a cut flower. Spring bloom continues through summer, and can actually continue sporadically for as long as the weather is warm.

Warm Season Bedding Plants Begin

Alyssum grows very readily from seed.

Annual bedding plants are surprisingly more popular among those who enjoy gardening less. Those who procure the services of gardeners appreciate the rich colors and simple efficiency of annuals. Many who are more directly involved with their gardening consider them to be decadent. Nonetheless, warm season bedding plants will soon be in season.

Cool season bedding plants should perform well until the weather becomes too warm for them. There is therefore no rush to replace them yet. Besides, it is likely still a bit too cool for mature warm season bedding plants to be out in the garden. However, seed for warm season bedding plants takes time to grow. Some should start now to be ready for spring.

For example, petunia, impatien and zinnia are some of the most popular of warm season bedding plants. Almost all of them arrive at their respective gardens as somewhat mature plants within cell packs from nurseries. Presently, such plants may be vulnerable to frost. However, seed of these plants that begin now should start to grow after the threat of frost.

Not many of even the most avid of garden enthusiasts grow these popular warm season bedding plants from seed. Yet, a few do so. Some unusual or rare plant varieties are only available as seed. Many common wildflowers and ‘true to type’ annuals provide seed for subsequent generations. Such seed generally start in flats with shelter from frost indoors.

From flats, seedlings may graduate to cell packs or small pots prior to transitioning into a garden. Some should actually begin within cells rather than flats. Seedlings relocate into a garden when adequately mature, whether from flats, cells or pots. Seed for many warm season bedding plants perform best directly in the garden though, without transplanting.

Nasturtium seedlings do not grow well within the confinement of cells. Then, they remain somewhat pekid for a few days while they recover from transplanting into a garden. They grow so much more efficiently from seed sown directly into a garden. Marigold can grow about as well from seed directly in the garden as they can as seedlings that grew in flats.