Annuals Change With The Seasons

50930thumbLike it or not, the warm season annuals that were so flashy all through spring and summer will eventually need to be replaced with cool season annuals to provide color through winter. It is always unpleasant to pull up the annuals of a previous season while they are still blooming, even if they are already getting scruffy and discolored. It is actually easier if they got roasted by recent warmth.

Some warm season annuals last longer than others. Many are actually perennials that can be overplanted with new cool season annuals as they get cut back or go dormant through their ‘off’ season. Some cur back perennials may not survive through winter; but those that do can regenerate next spring, just as the cool season annuals that obscured them all winter are finishing.

Wax begonias, for example, are warm season annuals that can continue to bloom until they get frosted. Where sheltered from frost, they only need to be cut back because partial defoliation exposes knobby bare stems. If they can be hidden by pansies or violas through their bare phase, they never need to be removed, and some will be happy to regenerate in spring.

Conversely, cyclamen, sweet William, chrysanthemum and some primroses are cool season annuals that have the potential to survive under the lush growth of warm season annuals next summer; but that is a topic for later. (Some people are allergic to primroses like poison oak.) Iceland poppy and ornamental cabbage and kale are not so perennial, but are quite colorful through winter.

Alyssum and nasturtium really are annuals that do not survive much more than one year. However, they can perform through summer where sheltered from heat, or through winter where sheltered from cold. In ideal situations, their self sown seedling replace deteriorating older plants, so that they can perform throughout the year. Nasturtium should be planted as seed, not from cell packs.

Calendula is a popular cool season annual early in the season, but may not last through the end of winter. Yet it is popular because it is so excellent through autumn. Chrysanthemums are even flashier, although they are often replaced as soon their first bloom phase finishes.

Start Cool Season Annuals Early

30925Twice a year, it becomes necessary to discuss the unpleasantries of pulling up the flowering annuals (as well as vegetable plants) of one season, to relinquish space for those of the next season. Just a few months ago, cool season annuals got replaced with warm season annuals. Now, those same warm season annuals will get replaced with cool season annuals for the next few months.

It is unpleasant because the outgoing annuals are probably still blooming when it is time for them to go. It might be easier to wait for cool season annuals to get roasted by hot weather, or for warm season annuals to get frosted. Unfortunately, by that time, the incoming annuals would be at a disadvantage. Hot or cold weather is also uncomfortable for plants that are not yet established.

Sure, warm season annuals like warmth, but only after they have sufficiently dispersed their roots to sustain their growth during warm weather. This is most efficiently accomplished while the weather is still mild earlier within their season. Cool season annuals likewise do not mind cool weather, but do not grow as well as they do during the warmer weather earlier within their season.

This is why it is better to plant pansy, viola, sweet William, Iceland poppy, stock, calendula and the various primroses earlier rather than later if possible. There is no exact science here. A forecast for warm weather certainly justifies delay. Cyclamen and ornamental cabbage and kale are a bit more sensitive to warmth, so could wait a bit longer. They grow well through cold weather anyway.

Chrysanthemum, alyssum and nasturtium are odd ones. Chrysanthemum, although perennial, is most often planted as a short term autumn annual while it is already blooming or is just about to bloom. It rarely gets a second chance if it finishes bloom before winter. Alyssum and nasturtium can be both warm and cool season annuals. They only gets replanted this time of year because individual plants perform through one season or the other, but probably not both. Nasturtium should be grown from seed.

Fernleaf Yarrow

70830‘Moonshine’ is probably the epitome of fernleaf yarrow, Achillea filipendulina, even though it is technically a hybrid. From the middle to the end of summer, its three inch wide corymbs (flat-topped trusses) of tiny bright yellow flowers stand as high as three feet above ferny and gray basal foliage. Bloom is best in full sun and warm exposure. Established plants do not need too much water.

Most varieties of fernleaf yarrow also bloom with bright yellow or gold flowers. Some might bloom with pale yellow, rosy pink, pale pink, reddish, white or pink and white flowers. All are good cut flowers, and can be dried. Some varieties are more compact. The most compact varieties work nicely in planters of mixed perennials. Butterflies and hummingbirds find them wherever they are.

Pruning out deteriorating blooms may promote sporadic subsequent bloom until autumn. However, some plants may bloom all at once, and then not bloom again until the following summer. Large blooms on the most vigorous plants may need to be staked. New plants can be propagated by division from mature plants. ‘Moonshine’ and many other cultivars are sterile. Others might self sow.

Cosmos

80905Their 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.

Cockscomb

80822Not all annuals last as long as petunias do through summer, or pansies do through winter. Some fill in for the in between seasons, or if longer term annuals do not last quite as long as they should. Cockscomb, Celosia plumosa, blooms best now that it is about halfway through summer, and then finishes as weather gets too cool for it in late autumn, not so much more than two months later.

The common name of cockscomb is actually derived from another species, Celosia cristata, which blooms with oddly stunted and flared blooms that supposedly resemble the combs of roosters, but the most popular varieties are so stunted that they actually look more like little fuzzy brains. Celosia plumosa blooms are more feathery, like those of pampas grass, but only three inches long.

The red, orange, yellow and pink blooms are as brightly colored as a pinata. Mixed colors, which might include softer pink, are the most popular for six packs and seed. White is notably lacking from popular mixes, and is only rarely available separately. Some varieties have bronzed foliage. Cockscomb lasts more than a week as a cut flower, but blooms on rather short and stout stems.

Busy Lizzie

80801In only a few years, busy Lizzie, Impatiens walleriana, went from being one of the most popular warm season annuals to being unavailable in nurseries. It is now making a slight comeback. Most of those planted during their planting season last spring are now so profuse with bloom that their rich foliage is mostly obscured. Although they can be perennial, almost all get replaced in autumn.

The problem associated with their unavailability was that a type of downy mildew that is resistant to common fungicides had become a temporary epidemic among the growers who supply the plants. The disease is still out and about, so can still infect busy Lizzie, but is not such an epidemic after a few years of scarcity of host material for it to infest. Nonetheless, busy Lizzie is still risky.

Bloom is clear and cheery hues of pink, red, magenta, peachy orange, pale lavender and white. The five petaled flowers are about an inch or two in diameter. Leaves are a bit bigger than the flowers. Foliage and stems are succulent and very fragile, so will not tolerate traffic, and will die in winter if exposed to frost. The biggest plants can get almost two feet tall and three feet broad.

Annuals Just Might Be Perennials

70614thumbAnnuals come and annuals go. There are cool season annuals for winter. There are warm season annuals for summer. Really though, there are all sorts of annuals that are not annuals at all. Most are some sort of perennial that has the potential to last longer than a single season. Only a few popular ‘annuals’ would necessarily die after blooming and producing seed, within a single year.

To be clear, true annuals last only a single year. They probably germinate from seed early in spring, and grow quickly. They then bloom in spring or at least by summer, and subsequently produce seed. Once their seed has matured and been dispersed, their job is done. They finally die in late autumn or winter. Annuals from deserts are even faster because of the harshness of the weather.

Many large-flowered sunflowers are true annuals. They are finished once their seeds mature. They will not bloom again. Even if they wanted to, they would not survive through winter. Petunias should be annuals, because they also die over winter. However, it is possible for them to survive winter in a semi-dormant state, and regenerate and bloom again the following spring and summer.

Realistically, it is not practical to salvage petunias for a second year. It is easier and more efficient to plant new ones. Yet, it sometimes happens, particularly in mixed plantings where old plants can get cut back while cool season annuals dominate in winter. Alternatively, lanky old stems can get buried with only their tips exposed. These tips might grow as new plants the following spring.

Cyclamen are cool season annuals that have been dieing back for summer. They usually get removed by now. However, in mixed plantings, some of their fat tubers can survive through summer to regenerate next autumn. For what they cost, they are worth salvaging! Primrose, chrysanthemum, impatiens and the various fibrous begonias are all worth salvaging through their off seasons.

Fibrous begonias may not know what their off season is. Those that bloomed through winter might be looking tired by now. If pruned back, they could regenerate as warm season annuals. Those planted in spring might look tired by the end of summer. If pruned back early enough in autumn, and protected from frost, they might grow enough before winter to work as cool season annuals. Cutting them back and waiting for regeneration may not be much more effort than replacing old plants with new ones, and is less expensive.

Annual Gazania

80620Why would anyone want to grow annual gazania when perennial gazania that is popularly grown as ground cover lasts for several years? Well, as long as the weather stays warm, annual gazania blooms with an impressive abundance of bigger and more brightly colored flowers. Perennial gazania blooms less profusely and only in midsummer, with simpler and somewhat smaller flowers.

Flowers are warm shades of orange, red, yellow, pink, beige and white, typically with intricate patterns of stripes and spots of other colors of the same range, as well as chocolatey brown. Each upward facing daisy flower is as wide as three inches or maybe four. They close up at night and during cloudy weather, and stay closed briefly in the morning until they warm up a bit in the sunlight.

Mature plants typically do not get much more than six inched deep, but can get twice as deep if crowded. They have no problem getting nearly a foot wide though. Foliage is only slightly bronzed; not quite bronze, but not rich green either. The pretty gray undersides of the leaves are obscured from view by the density of the foliage. Gazania needs full exposure, and is quite tolerant of heat.

Six on Saturday: Petunias

 

These were only recently planted, within the past few weeks, so are not completely filled in. That of course is unimportant for pictures of only the flowers close up. I have not grown petunias for many years, but I am getting to like these because they are so colorful in the sunnier spots. There are busy Lizzy in the shadier spots. (I can explain that later.) It is not easy to select a favorite. Although the white petunia should be my favorite, I really like how brightly colorful the first one ‘Dreams Sky Blue’ is on the side of the road. ‘Blue Madness’ and ‘Red Madness’, the second and third pictures, are so reminiscent of petunias that we grew many years ago, and might even be the same. The unknown petunia in the fifth picture is the only one here that I do not like much, and it did not work out as well as hoped anyway. It is planted in hanging pots, but does not cascade. That is why a few ‘Wave Lavender’ in the fourth picture were added in with them. The white petunia happens to be only one of a mix of various colors.

The first three were planted in beds at ground level. The fourth was planted both in an elevated planting bed, and added to hanging baskets with the fifth. The fifth was the first to be planted in the hanging baskets, but is not cascading as expected. The sixth, along with a variety of other colors, is in a few large planter boxes, so will hopefully cascade somewhat, but does not need to.

1. Dreams Sky BlueP80609
2. Midnight MadnessP80609+
3. Red MadnessP80609++
4. Wave LavenderP80609+++
5. This variety is unknownP80609++++
6. This variety is unknown and includes a mix of colors.P80609+++++
This is the link for Six on Saturday, for anyone else who would like to participate:

https://thepropagatorblog.wordpress.com/2017/09/18/six-on-saturday-a-participant-guide/

Verbena

80613This is one of those warm season annuals that we do not hear much about. Verbena looks something like lantana, but rather than maturing into a nice shallow ground cover or low mounding shrub with a bit of staying power, verbena lasts only until frost next autumn. The blooms are a bit larger. The leaves are a bit greener. They stay lower than a foot, and get only a few inches wider than tall.

Floral color was already impressive decades ago when it was limited to white and rich hues of blue, red, purple and pink. Even more hues and shades are available now, as well as peach, rose, lavender and many bicolored varieties. The tiny flowers are arranged in small and dense trusses, with the outer flowers opening and fading to lighter hues before the inner flowers opening darker.

Bloom is best in full sun exposure. A bit of partial shade should not be a problem for those that cascade from planter boxes up against a wall, or pots that hang from eaves. Verbena is popularly grown as a cascading component of mixed plantings in large pots, urns and elevated planters, often in conjunction with more upright plants. Verbena works nicely for small scale bedding as well.