It is fair to say that garden verbena, Verbena X hybrida, is a reliable warm season annual. It gets planted in spring to spread out and bloom through summer with bright pink, red, purple or almost blue, or softer pastel pink or pale white. It is commonly replaced with cool season annuals by late autumn. However, garden verbena is actually a short term perennial that can survive winter to bloom for a few years.
Perhaps individual plants do not last long enough to be practical as permanent ground cover. Yet, if mulched just so, the thin branches can root where they touch the ground, and then grow into new plants to replace the original plants before they die out. Stems do not spread or cascade much more than a foot from where they are rooted. Nor do they stand more than six inches deep.
Oh, how breeding complicates things. Many years ago, there were only six basic types of wax begonia, Begonia semperflorens-cultorum, with three choices for floral color, and two choices for foliar color. Bloom was white, pink or red. Foliage was either green or dark bronze. Although these choices have not changed, some modern hybrids are difficult to distinguish from other species.
Wax begonia can be either a cool season annual or a warm season annual, depending on when it gets planted. It can be grown as a short term perennial if pruned back in both early spring and early autumn. By spring, winter growth is tired of the cold. By autumn, summer growth is worn out from warmth. Exposed plants can get lethally frosted in winter or roasted by sunlight in summer.
Therefore, wax begonia prefers to be somewhat sheltered. It is more tolerant of full sun exposure in summer if mixed with other annuals or perennials. Too much shade compromises bloom. Wax begonia expects richly amended soil and regular watering, and is just as happy in pots as other annuals are. Potted plants can be moved to sheltered spots when the weather gets too hot or cold.
The flowers may not last very long once cut, but cosmos, Cosmos bipinnatus, blooms so abundantly, that there might not be any shortage of new flower to cut and bring in to replace those cut a day or two before. Their pastel pinks and lavenders, as well as white, suit the Easter season perfectly. Their soft light green foliage is remarkably lacy. Mature plants are about two to four feet tall.
‘Seashells’ has distinctively tubular petals (which are actually ray florets around the perimeter of each composite flower). ‘Daydream’ flowers each have a typical yellow center surrounded by a pink inner ring, which is surrounded by a lighter outer ring. ‘Sensation’ is a mix of tall varieties. ‘Versailles stays less than three feet tall. The popular ‘Sonata’ series stays less than two feet tall.
Cosmos likes full sun, somewhat rich soil, and regular watering. If it is happy enough, it can self sow.
Pulling out cool season annuals that are still somewhat colorful is never easy, even if they are already deteriorating. There is always the desire to stretch their season as late as possible until they succumb to warmer weather. Only a few can perform all year, or get cut back to hide below other taller plants until the weather gets cool enough in autumn for them to regenerate and bloom again.
Regardless of all the resistance, removing the annuals of a previous season relinquishes space for annuals that are appropriate to the next season, whether cool to warm season, or warm to cool season. Even if new annuals are initially wimpy relative to the older annuals that were removed, they should proliferate and bloom better than lingering unseasonable annuals would if not removed.
Timing is somewhat important. There is no point in removing cool season annuals too early if the weather is still too cool for warm season annuals. However, there is no point in planting too late either. Delayed planting only delays growth and bloom. Some warm season annuals, especially those grown from seed sown late in winter, prefer to get established while the weather is still cool.
French marigold is probably the most traditional warm season annual for bright yellow, orange and bronze. Lobelia contrasts excellently with rich blue and purple, and can also be purplish rose or white. Petunia can do even more with brighter and more variable colors. Cosmos provides pastel pinks and white on taller plants. Cockscomb colors rival those of marigold, and can also be red.
Pincushion flower, annual statice and zinnia are popularly enjoyed as bedding plants, and also work well individually, behind lower bedding plants, or in planters of mixed annuals or perennials. Verbena and moss rose cascade nicely from such mixed planters. Sadly, brightly colored and formerly popular busy Lizzie (impatiens) are either rare or unavailable because of a mold disease.
Nasturtium and alyssum are warm season annuals that are often grown through winter as well. Where they are allowed to naturalize and bloom throughout the year, deteriorating old plants might need to be groomed out as they get replaced by self sown plants. New nasturtium should be sown as seed, instead of planted as seedlings from cell packs. Alyssum grows well by either means.
The same cooling weather that is initiating fall color is what finishes the zinnias that bloomed so colorfully through summer. Like tomatoes, they can stay out in the garden until they succumb frost if they continue to perform, and if the space they occupy is not needed for something else. There should be no guilt with replacing them sooner. After all, they are technically warm season annuals.
Some of the more popular types of zinnias are identified as Zinnia elegans or Zinnia violacea. Most are known merely by their variety name. They have been bred so extensively than it is difficult to assign any of them to particular species. Most are susceptible to mildew if crowded or watered from above. They want full sun exposure and rich soil. Seed can be sown immediately after frost.
Zinnias are crazily variable. Some get more than three feet tall. Others are less than a foot tall. They can bloom in every color except blue. Some resemble other types of daisies, with distended centers. Others are as fluffy as African marigolds. Some bloom with small but profuse flowers. Others have fewer but bigger flowers that are wider than three inches. Most are excellent cut flowers.
French Marigold might have been a more appropriate choice. It is the official flower of Dia de los Muertos on November 2. Some might say that the bigger and bolder African marigold, Tagetes erecta, is just as official. Both are Mexican, but as the names imply, most varieties of French marigold were developed in France, and most varieties of African marigold were developed in Africa.
Both African and French marigolds are warm season or autumn annuals that exhibit a similar range of floral colors that contrast nicely against their rich green aromatic foliage, but they are not much more similar than that. African marigold can get almost three feet high and two feet wide. Its bigger pom pom flowers tend to be solid colors rather than mixed; and vanilla white, although unpopular, is not rare. Bright yellow and bright orange are the most familiar. Rusty red is the third most popular color.
African marigold wants rich and well drained soil in sunny exposures. It gets lanky, blooms less, and is more likely to mildew where partly shaded. It should be watered regularly and early in the day. Flowers can mold if they stay damp for too long. Deadheading, which is the removal of deteriorating flowers, promotes continued bloom. Occasional application of fertilizer might also help.
They are really just smaller versions of the larger perennial dahlias that are grown for their big bold flowers and flashy colors. Technically, annual dahlias produce smaller versions of the same perennial roots that can survive through winter to regenerate the following spring. Yet to most of us, it is easier to purchase new plants in spring than to grow new plants from stored roots.
Relative to larger dahlias, everything about annual dahlias is subdued. The flowers are neither as big, nor as variable. They can bloom any color except blue or green, but are usually simple shades of red, orange, yellow, pink or white. Their main advantage is that they do not get much more than a foot tall, so they fit into more situations and do not need to be staked.
Bloom starts rather late in spring and continues until about now. Some varieties have bronzed foliage. Fertilizer promotes bloom and healthy foliar color; but too much nitrogen can inhibit bloom. Dahlias can be happy in pots, but only with good drainage and regular watering.
Gazanias were not planned. The English daisies that were planted last spring as warm season annuals that might hopefully continue as perennials succumbed to rust. Seriously! This rust was nasty! I had no idea that English daisy was so susceptible to rust! They were so ugly that they needed to be removed. They were replaced with the gazanias a bit more than half way through.
Gazanias are not the flashiest of choices for the prominent planters that they went into, but they work. If they continue to bloom through winter, they can stay as long as they like. If they stay long enough to get bald spots, we can trim around the edges and plug the scraps back into the bald spots. I would rather put a bit of effort into maintaining them than replace them as the seasons change.
These pictures were taken about two weeks ago, along with the picture of the gazania that was posted last week. For some unknown reason, the gazanias are presently taking a break from blooming.
1. White is actually not my favorite color for gazanias. Yes, white is my favorite color. I just think that gazanias are at their best in brighter colors like yellow and orange. This white is not the best anyway. It looks like very pale yellow to me.
2. Yellow, in conjunction with orange, is one of the two classic colors for gazanias, and is one of my two favorites . . . in conjunction with orange.
3. Orange is the other half of the caption to the picture above. (Just read the same caption, and switch ‘yellow’ for ‘orange’, and ‘orange’ for ‘yellow’.)
4. Pink might really be light burgundy. It was a bit darker when it first bloomed. This might be one of those colors that only girls can identify.
5. Yellow with red stripes looks like something that blooms in the garden of Ronald McDonald.
6. Cream with burgundy stripes looks like something that blooms in the garden of a clown with slightly more discriminating taste.
This is the link for Six on Saturday, for anyone else who would like to participate:
Their pastel hues and blends of pink, lavender, near red and white are so perfect for the middle of spring when cosmos, Cosmos bipinnatus, begin to bloom. They are just as perfect as bloom continues right through summer and almost to autumn, when the tall and airy plants finally begin to wear themselves out. If they continue through autumn, they eventually succumb to frost in winter.
Individual flowers are as delicate as they look, but are prolific. New flowers replace older flowers a quickly as they fade. Deadheading promotes even better bloom. A few of the last flowers to bloom can be left as the season ends to sow seed for next year. However, fancy cultivars are not true to type, so subsequent generations will be more like the basic specie, with simpler flowers.
Cosmos likes full sun exposure, rich soil and regular watering. Mature plants are about two or three, or even four feet tall, although the most popular varieties stay shorter and more compact. The species name of ‘bipinnatus‘ refers to the pinnate leaves that are divided into very narrow lobes that are also divided into even narrower lobes. The collective foliage is very delicate, lacy and airy.
Good old fashioned busy Lizzie is hard to find nowadays, if it can be found at all. The nasty mildew that kills it so quickly might not be prevalent everywhere, but happens to be a serious problem where most of the bedding plant farms are located. Now, the formerly uncommon New Guinea impatiens, Impatiens X hawkeri, which is somehow resistant to the mildew, is becoming popular.
The two specie have distinct personalities though. Busy Lizzie dazzles with cheery cartoonish colors, and bloom profuse enough to almost obscure the light green foliage. New Guinea impatiens has bigger and bolder flowers of white, pink, red, magenta, lavender, purple, apricot and reddish orange, but does not try to hide its rich green, bronze, purplish bronze or gold variegated foliage.
New Guinea impatiens are more expensive, and are not available in cell packs like most other bedding plants are. They are most popular in four inch pots. They do well in pots and tolerate partial shade, but want rich soil and regular watering. Mature plants can get more than a foot wide, and might get as tall if crowded. Although grown as annuals, they can survive as short term perennials.