African Daisy

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African daisy excels as bulb cover.

They are more than just shrubbier and more colorful versions of the formerly stigmatized trailing African daisy. Modern African daisies are actually various hybrids of several other species. Extensive breeding complicated their lineages enough for them to be known by cultivar names rather than by species names. To one degree or another, most are probably related to Osteospermum ecklonis.

These fancier modern hybrids of African daisy grow as annuals in harsher climates. If planted just after the last frost date, they bloom splendidly for early spring, and continue to bloom sporadically through summer. If they grow and bloom a bit too well, they may like to be trimmed back to bloom some more. Locally, they persist through winter as short term perennials, to bloom as winter ends.

Bloom provides pastel hues of yellow, orange, pink, ruddy pink, lavender, purple or white. Early spring bloom is most profuse, particularly for fluffy plants that were not trimmed back over winter. The biggest sprawling plants should get trimmed back after bloom. Subsequent sporadic bloom, mixed with random profuse phases, is inhibited only by warm summer weather and cool winter weather.

African daisy wants full sun and regular watering. Mature plants get about two feet deep and broad. If pressed into the soil, outer stems can develop roots to grow as new plants, as the original dies.

Deadhead To Eliminate Fading Bloom

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Deadhead finished daffodils to conserve resources.

The need to deadhead so early in spring is one of the few minor consequences of spring bulbs. Long before it becomes necessary to deadhead zinnia, canna and rose, the first flowers to bloom as winter ends are already finished. Many are those of spring bulbs. Their lingering deteriorating bloom can be slightly unappealing. What is more of a concern, is that some will likely try to go to seed.

The process of producing unwanted seed consumes resources that could otherwise sustain more useful growth. However, for spring bulbs that have finished blooming, production of seed for a new generation is more important than their own survival. That is why it is helpful to deadhead bulbs and many other plants after bloom. If deprived of seed production, they divert resources elsewhere.

Deadheaded narcissus, daffodil, freesia, lily and tulip store more resources into new bulbs, which they generate to bloom next year. Snowdrop and grape hyacinth cultivars that get deadheaded are not likely to get overwhelmed by their own feral seedlings. (It is neither practical nor necessary to deadhead crocus or big naturalized colonies of snowflake, feral snowdrop or feral grape hyacinth.)

While it is important to deadhead most spring bulbs after bloom, it is also important to not remove deteriorating foliage prematurely. After all, the foliage produces the resources that are necessary to generate healthy new bulbs for next year. Such foliage starts to slowly deteriorate immediately after bloom, but may linger for many months. Bulbs will shed their foliage when they no longer need it.

Until then, bedding plants or low perennials can obscure deteriorating bulb foliage as it falls over. Trailing gazania and dwarf periwinkle work nicely for shorter bulbs. If they get shorn low for winter, trailing plumbago, common periwinkle and African daisy can work nicely for taller bulbs.

Not So Annual

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These primrose look as good as they did last year.

Among cattle, a cow is a female who has calved. Prior to that, she was a heifer. A bull is an adult male. A bullock is a juvenile male or castrated bull. Most cattle are males who were castrated while young, and are known as steers. Yet, cattle are commonly known collectively as ‘cows’.

Similarly, bedding plants are commonly known collectively as ‘annuals’. Many really are annuals. However, some are biennials; an even more are, to some degree, perennials.

Replacing annuals annually make sense. They grow, bloom and die within one year. Some sow seed to regenerate if and when they get the chance. In the prominent spots of our gardens, not many are likely to get such a chance before they are replaced by other annuals for more immediate gratification within the next season.

The same applies to bedding plants that have potential to perform as perennials. They too get replaced during their off season. Since most are inexpensive, their untimely collective demise is not considered to be too terribly wasteful.

There are a few that are not so easy to part with. Cyclamen will be a topic for next week because it is a cool season perennial that is too expensive to be deprived of its potential to regenerate and bloom next autumn and winter.

These English primrose from last winter were afforded an opportunity to stay in their landscape while they were somewhat dormant through the warmth of last summer, so that they could regenerate last autumn and bloom through this winter. A few from around the edges were moved inward to replace a few that did not survive. Impatiens were planted in front for summer.

The results are not exemplary only because of the shade, but are worth the effort of not putting effort into replacement.

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Two seasons for the price of one.

Canna

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Cannas are just dormant rhizomes now.

It is difficult to document the lineages of the countless modern garden varieties that have been hybridized from ten species of Canna. Straight species that are popularly grown within their native ranges are rare here. Some species are grown for their thick edible rhizomes. Many are grown for edible foliage. Some are employed to absorb toxins from contaminated riparian environments.

Garden varieties that are popular here are grown merely for their aesthetic appeal. The lushly big leaves are typically rich green, but might be bronzed, dark purplish bronze, or striped with yellow, bronze, creamy white or peachy pink. Large varieties get taller than eight feet. Compact types stay less than three feet tall. All foliage dies to the ground after frost, and grows back fast in spring.

The flashiest parts of canna flowers are actually very specialized stamens known as staminodes, which mostly obscure the very subdued petals and sepals. Red, orange, yellow, pink, salmon or very pale yellowish white bloom may be spotted or blotched. Flowers might be thin and wispy, or rather floppy and lush. Canna are popularly known as canna lilies, but are not at all related to lilies.

Bulb-Like Perennials For Summer

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Dahlias planted now bloom in summer.

Like something of bad science fiction, they are back. The earliest of spring bulbs that were so discourteously buried in shallow graves last autumn are making their presence known. Even before the weather gets noticeably warmer, their foliage emerges above the surface of the soil. Daffodil, narcissus, crocus and snowdrop are already blooming. Hyacinth, tulip and anemone will be next.

We know them as spring bulbs, or alternatively, as hardy bulbs. However, in this climate, many bloom through late winter, so are finished by spring. Also, many are technically not really bulbs. They might be corms, rhizomes, tubers or tuberous roots. They are hardy bulbs because they want to be planted through autumn so that they can get a bit of chill through winter before their early bloom.

Some spring bulbs require a bit more of a chill than they get in the locally mild climate. They bloom very well in their first season because they are pre-chilled before they are sold. Once dormant, they get dug and chilled in refrigeration to entice them to bloom well for subsequent seasons. That happens much later in the year though. For now, long before spring, we get to enjoy their bloom.

Summer bulbs, which are not so hardy, are what gets planted about now. Their planting is delayed, not just because they do not need chill, but also because they dislike it. If their foliage develops too early, it can be damaged by late frost. Once established, summer bulbs are more resilient to minor frost damage of premature foliage. They can therefore remain in the garden for many years.

Canna, dahlia and big old fashioned white calla are the simplest of summer bulb-like perennials to plant now. Those that are already established can be divided if crowded. The smaller and more colorful callas can be a bit more finicky. Gladiolus and various lilies are spectacular, but bloom only once annually, rather than throughout summer. They are also unlikely to establish as perennials.

Bulb-like perennials that bloom only once might be planted in phases to prolong their potentially brief bloom season.

Black Mondo Grass

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The foliage really is this dark.

The deeply colored foliage of black mondo grass, Ophiopogon planiscapus ‘Nigrescens’, is about as convincingly ‘black’ as foliage can get. It is darker than bronze New Zealand flax, purple leaf plum or bronze coral bells. Only purple beech or chocolate coleus are comparable. The foliage is dark enough to contrast very well against lightly colored planters or gray concrete, so works well in urns or mixed perennials, and bordering walkways. If it gets enough sunlight, black mondo grass makes a nice small scale ground cover under Japanese maples.

Mature plants stand only about half a foot tall, and spread slowly. The happiest plants can get nearly twice as tall. The softly cascading leaves are only about a quarter inch wide. Small spikes of tiny pink flowers that sometimes bloom in summer would contrast nicely against the dark foliage, but are rarely seen above the foliage. Black mondo grass prefers rather rich soil and somewhat regular watering. However, as they disperse roots, older plants do not seem to mind too much if they briefly get a bit dry.

Corm-ucopia

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Is this part of the secret to their success?

Montbretia showed up here several years ago. Of course, it did not take long for it to get very established. It is too shady for bloom, but not shady enough to inhibit vegetative proliferation. Those nasty stolons get everywhere, and grow into corms. They are so aggressive that they exclude English ivy! Seriously, they are the only species we know that can crowd out English ivy!

Some consider Montbretia to be the the genus name. Some consider it to be a common name for the genus of Crocosmia, or for a particular intergeneric hybrid. What is now so aggressively naturalized here might be Crocosmia paniculata. I really do not know. The few rare and sporadic blooms look like what I am familiar with in other landscapes, with branched inflorescences.

Now, I am aware of how aggressive their stolons are, and that their stolons swell into corms when they get to where they are going. I also know the physiology of simple corms, and that new replacement corms develop on top of old deteriorating corms. They might extend a few more stolons in the process, or put out a litter of cormels off to the side, but their technique is limited.

Well, it should be.

The technique demonstrated by this picture is weird. It seems to show a series of corms from the last twelve years. That makes sense if one corm replaces a previous corm annually. Longer accumulations can be found in older colonies. However, montbretia infested this landscape less than a decade ago, and took a few more years to disperse where these corms were unearthed.

Furthermore, after a decade, the oldest corms should be rotten and decomposed. Except for the stunted four year old corm, those that developed in the last six years seem to be suspiciously fresh.

Some Annuals Are Not Annual

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Some summer annuals can survive winter.

So many annuals are actually perennials. They just get dug and replaced because they are not pretty enough during their off season. For warm season annuals, winter is the off season. For cool season annuals, summer is the off season. However, if left alone, many annuals that are actually perennials go dormant so that they can survive through their off season to regenerate and perform again for another season, or several seasons

Cyclamen and various primroses are cool season annuals that are in season now. Cyclamen will go dormant and defoliate as the weather gets warm in summer. Primroses do not defoliate, but get rather runty through warm weather. If planted with other light duty warm season perennials that take over for them, no one notices. For example, primroses are colorful enough now to distract from tired fleabane. By the time primroses fade, the fleabane takes over.

Chrysanthemums are among the flashiest of perennial annuals, but also have a short season. They typically get planted while blooming in autumn, but finish their bloom cycle before winter. After all the rain and cool weather . . . and then a bit of warm weather, some are already dying back to the ground; but closer examination might reveal new growth already emerging from the roots!

Nasturtiums can obscure regenerating chrysanthemums nicely. If the frost sets them back, they recovery quickly. They will bloom more colorfully by spring, and continue until summer gets too warm. By that time, the chrysanthemums should be filling out nicely to bloom by autumn. As the chrysanthemums finish, the nasturtiums will have sown their seeds, so that the process can start over again. Neither chrysanthemum nor nasturtium need to be removed while out of season. They only need to be pruned back and groomed accordingly.

Coleus, impatiens, fibrous begonias and maybe even polka dot plant that were only moderately damaged by frost might be salvageable if they can stay put long enough. That is the advantage of growing them in pots with other small perennials that will cover for them when they die back or need to be pruned back.

Unidentified Cyclamen

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What species is this naturalized Cyclamen? hederifoliumcoum – feral persicum – or something else?

Could this be Cyclamen hederifolium? Perhaps it is some sort of Cyclamen coum, or possibly feral Cyclamen persicum. I really do not know. Common florists’ cyclamen is the only cyclamen that I have any experience with. I grew it as a perennial when I was in high school, but never saw any feral colonies growing from self sown seed. I have never met the other species before.

Several colonies of this naturalized species of Cyclamen grow wild in the garden of a colleague. No one knows how they got there. I noticed them while procuring specimens of what might be other species that I have been wanting to grow, even though I am not certain of their identities either. I suspect that one could be Sorbus americana, and that another could be Rhus glabra.

I have been wanting to try growing Cyclamen hederifolium or Cyclamen coum since I saw it in pictures of home gardens in other regions. It looks something like common florists’ cyclamen that I enjoyed growing so many years ago, but more natural and relaxed. As much as I like florists’ cyclamen, the brightly colored flowers look a bit too synthetic for naturalistic landscapes.

Even though interesting species of Cyclamen have been available online and from mail order catalogs for at least the past several years, I have been hesitant to try any. I just do not know if they would be happy in forested landscapes where I want to grow them. Not many perennials perform well with so much overwhelming and mildly toxic debris from redwoods and live oaks.

Now I can see that they perform well enough here to naturalize, even under big and messy coast live oaks. In fact, I am now concerned that they have potential to become invasively naturalized in surrounding forests.

Florists’ Cyclamen

91218It is unfortunate that most florists’ cyclamen, Cyclamen persicum, are enjoyed as cool season annuals only through winter, and then discarded as they are replaced by spring annuals. They can actually survive as perennials for several years, with white, red, pink or magenta flowers hovering above their marbled rubbery foliage each winter. Foliage typically stay less than six inches deep.

Florists’ cyclamen are probably typically discarded seasonally because, after blooming through winter, they take some time to redirect their resources to adapt to their landscape situations as the weather warms through spring. During that time, they can look rather tired. Shortly after they recover, they defoliate for dormancy through the warmth of summer. Some do not survive the process.

When they regenerate through the following autumn, they are not as uniform as they were when first installed. This is probably not a problem where a few florists’ cyclamen are planted with mixed annuals or perennials that compensate for their irregularities as well as their dormancy through summer. However, it does not work well for the uniform flower beds that they are often installed into.