Deadheading Promotes And Prolongs Bloom

90612thumbApril showers bring May flowers. May flowers make a mess. Well, some of them do. Most simply disintegrate and fall from the trees, shrubs and vines that produced them, and decompose into the soil below. Some might have needed to be swept off of pavement and decks. Regardless, most of us do not notice the very minor consequences for the majority of spectacular spring bloom.

However, there are some flowers that demand a bit more attention after they finish blooming. They linger after the show is over, and can look shabby as they deteriorate. Small ones can simply be plucked. Larger blooms might need to be pruned out. The process of removing deteriorating blooms is known as ‘deadheading’, and it is done for more reasons than just to keep plants groomed.

Plants bloom to produce seed, and the production of seed takes resources. Removal of seed structures not only diverts resources to more useful functions, but for many plants, it also stimulates subsequent bloom in response to interrupted seed production. They literally keep trying until they are able to produce viable seed, even if they must continue all season until late autumn dormancy.

Most plants that benefit from deadheading are perennials. Shasta daisy, black-eyed Susan, blanket flower, cone flower, yarrow, lavender and beard tongue (penstemon) bloom more abundantly and for a longer time with regular deadheading. The various lavenders, as well as other perennials that are comparably shrubby, are easily deadheaded by shearing after profuse bloom phases.

For bulbs and bulb like perennials that bloom only once annually, deadheading will not promote subsequent bloom during the same year, but conserves resources for the following year. Daffodil, lily, clivia, various iris and, during summer, gladiolus and dahlia, all appreciate diligent deadheading.

Petunia and marigold are two annuals that happen to bloom better with regularly deadheading. They bloom so profusely that deadheading can be quite a chore. Plants that can be invasive, such as salsify, should be deadheaded before dispersing seed.

Roses Can Not Be Neglected

P80602+Roses are not for the meek. They are too demanding, too sensitive, too thorny, and without their flowers, they are not even very attractive. They have no business in a low-maintenance landscape, or in a landscape maintained by mow, blow and go gardeners. Those who want to grow rose plants for their flowers should be ready to give them what they want, and to prune them aggressively.

The most aggressive pruning gets done during winter dormancy. That process alone can be quite intimidating for those who are just getting acquainted with roses. After seeing them grow through the year, it seems counterproductive to prune big plants back to only a few short canes. Yet, by now, those canes should have produced much taller new canes that are already blooming profusely.

Now it is time to prune roses again, or will be time to do so soon. Deteriorating flowers need to be pruned away to promote continued bloom, a process known as ‘deadheading’. Otherwise, the fruiting structures that develop, known as ‘rose hips’, divert resources and inhibit bloom. Of course, blooms taken as cut flowers leave no hips, but they might leave stubs that may need grooming.

The popular technique of pruning back to the fifth leaf below a hip is not necessarily what roses want. It probably originated from the recommendation of pruning back to a low leaf with five leaflets because the buds associated with upper leaves with three or less leaflets are not as likely to develop into productive stems. However, pruning a bit too low is probably better than pruning too high.

When cutting roses to bring in, it is better to cut long stems, and then shorten them later if necessary. Each stem should be cut just above a leaf so that the bud in the leaf axil can develop into a new stem without much of a stub above it. The cut stem left behind on the plant should not be so long that it extends too far above the canes that were pruned over winter, or becomes crowded.

Crowded stems inhibit growth of vigorous blooming canes, and are more susceptible to rust, mildew and blackspot.P80602++

Spectacular Bloom Can Be Lethal

70510thumbAfter providing remarkably striking foliage for many years, the biggest and boldest agaves bolt with spectacularly tall floral stalks that support horizontal pads of flowers. These stalks can bloom for months, and stand for months after bloom is finished. Then things get ugly. The foliage around each bloom folds back, desiccates and dies. There is no nice way to describe it. Bloom is death.

Plants that bloom only once and then die are ‘monocarpic’. Agaves are not truly monocarpic, since they do not really die completely. They survive by producing pups (offshoots) as their original rosettes of foliage die. Some agaves start to produce pups years prior to bloom, just to be ready. Most terrestrial yuccas (that do not form trunks) go through the same process shortly after bloom.

Pups can be so prolific that they get crowded. Because the larger agaves are so big, they can conquer a significant area with just a few pups. With all their dangerously nasty foliar spines, extra pups are not at all easy to remove. Once removed, pups can be planted elsewhere as new plants, but they will grow up into even more agaves that will eventually bloom and make more pups!

Removal of the carcasses of bloomed yuccas without getting stabbed by the sharply tipped leaves is challenging. Removal of the carcasses of big agaves is hellish! Spines of old foliage never go dull. Pups hiding below the old foliage are just as dangerous. Tall blooms must be cut down like small trees. The debris can not be recycled in green waste, so must be disposed of like trash.

Furcraeas, which are related to agaves and yuccas, produce fewer pups, or may not produce any pups at all. Of course, a bloomed plant without pups will die completely. However, the huge conical blooms (that resemble Christmas trees) produce bulbils, which are tiny new plants that can be plugged back into the garden to grow into new plants! Regardless of all the work, furcraeas, as well as yuccas and agaves (within reason), are worth growing for their dramatic foliage and impressive bloom.

Splat!

P90310There are a few consequences to all this excellent rain. Gutters are flooding. Trees are falling. Mud is sliding. As much as we should be grateful for what we are getting while we are getting it, it is getting rather old. Clear and sunny weather that is forecast after today will be a welcome relief from all this muddy sogginess.
Almost all of the flowering cherries have somehow postponed bloom. It has not been unusually cold. It is as if the trees somehow know better than to bloom while so much unusually heavy rain is falling. Otherwise, they might have bloomed only briefly before the blossoms got knocked off. The buds are so fat that I expect they will begin to bloom by the middle of the week.
Only one flowering cherry that always blooms significantly earlier than the others bloomed on time, and is already finished. Considering how heavy the rain was during that time, the light duty bloom actually lasted impressively well.
Daffodils tried to delay their bloom as well; but some could wait no longer. Many were not bothered by the heavy rain. Others were knocked flat, and needed to be propped with small hoop stakes. Only some of those that were planted late in the planting season kept their buds closed this late.
I should be pleased that these hyacinth bloomed at all this year. They are the sort of bulbs that bloom only once in their first year, but then do not get sufficient chill in winter to bloom again. They must be in a cold spot. Unfortunately, it is also a shady spot. The floral stems stretched so much in the shade that they were easily knocked down by the heavy rain. Now they lay there like they have fallen and can’t get up.

Bloom Is Earlier If Forced

60224thumbProperly pruned deciduous fruit trees probably do not have too many extra stems to spare now. Neglected trees would have more to offer. Believe it or not, a few of us who prune deciduous fruit trees diligently and meticulously in winter sometimes leave a few unwanted stems to prune out and take into the home now that the flower buds are beginning to swell and are about to bloom.

Bloom accelerates once the bare twigs are inside where the nights are warmer than outside. If the buds are plump enough, they can bloom in a day or a few. (If not plump enough, the buds may desiccate before they bloom.) Twigs that are already blooming can be brought in as well, but do not last quite as long. Blossoms are a bit messy as they later drop petals, but are worth the bother.

The technique is simply known as ‘forcing’, which works something like forcing bulbs to bloom prematurely. Timing is critical. If a few blossoms are already blooming elsewhere on the tree, the fattest unblooming buds that are already showing color are ready to be cut and brought in. They only need to be put in a vase with water like any other cut flower, and can mix with other flowers.

Stone fruits (of the genus Prunus) like almond, apricot, plum, prune, peach, nectarine and cherry, start to bloom about now, although not in this order. Apple and pear bloom later. All their fruitless counterparts, known simply as flowering plum, flowering cherry, flowering crabapple and so on, are even more colorful, and some types bloom with ruffled double flowers. All bloom without foliage.

Flowering quince and forsythia have already bloomed, but would have been the most spectacular bare twigs to force into bloom. Pussywillow is probably the most familiar forced bloom twig. Hawthorn (Crataegus spp.) blooms something like pear, but the aroma may be objectionable to some. More adventurous garden enthusiasts force witch hazel (winter), redbud and star magnolia.

Warm Weather Confuses Dormant Plants

60217thumbClimate is what makes gardening so excellent here. It is just warm enough in summer for plants that like a bit of heat, but not too unbearably hot for too long. It is just cool enough in winter for plants that like a chill, but not cold enough for hard frost or heavy snow. The climate is also comfortable for us while out in the garden! Yet, even local climate is neither perfect nor predictable.

El Nino is still out there, and likely to deliver an abundance of rain. The rain last month was great while it lasted. This presently dry and warm weather in between has been excellent, but is likely to cause serious consequences. Some deciduous plants that are normally bare through winter are being deprived of adequate dormancy. Some are blooming prematurely, and may foliate soon.

When the rain resumes, it will ruin some of the premature bloom. This is generally harmless for most fruitless flowering trees like the various acacias, flowering plums and saucer magnolias, but compromises their most alluring feature. It can be more dangerous to flowering pears (including evergreen pear) and flowering crabapples, because wet blossoms can be infected with fire blight.

The more serious problem is that rain ruins blossoms and juvenile fruit of various deciduous fruit trees. Stone fruits such as almonds, apricots, cherries, plums, prunes, peaches and nectarines bloom first, and do so with delicate blossoms. If the blossoms do not get knocked off by rain, the juvenile fruit will rot if it stays damp too long. Many fruit trees are likely to lose all fruit this year.

Apple and pear trees should be safer because they bloom later, and bloom with more substantial flowers. (However, like their fruitless relatives, their wet blossoms are very susceptible to fire blight.) Persimmons and pomegranates bloom even later, and with even tougher flowers, so should be safe. Figs are in a league of their own, and should be fine if summer is warm.

Fortunately, destruction of bloom and fruit, although disappointing to us, is harmless to the affected trees.

Fringe Flower

51007Since modern cultivars became trendy several years ago, the old fashioned ‘common’ fringe flower, Loropetalum chinense, has become even more uncommon than it already was. It does not grow fast enough to function as large scale shrubbery, but slowly gets too big to work as small shrubbery. Without pruning, old plants take many years to get to fifteen feet tall.

The gracefully arching stems are outfitted with light green evergreen foliage. The simple leaves are about an inch or two long. The small white blooms have very narrow petals that hang downward like limp bits of ramen. Each bloom is actually a tuft of a few individual flowers. Bloom is most abundant in spring, and then continues sporadically through most of the year.

Modern cultivars of fringe flower are more compact, so rarely get more than five feet tall. Flowers can be white, pink, red or rosy pink. The most popular cultivars have purplish bronze foliage. Fringe flower does well as an understory plant, in the partial shade of trees. It should not be shorn, so should instead be pruned selectively to maintain its natural form.

Flowers Might Be Getting Scarce

70830thumbIt makes sense for flowers to bloom in spring. Winter is too cool, windy and damp for both flowers and the insects that pollinate many of them. By summer, successfully pollinated flowers have faded, are busy making seed to disperse in autumn. Some plants produce fruit to get birds and other animals to disperse their seed. There are certain advantages to blooming early in the spring.

Native plants that are endemic to chaparral climates are quicker with bloom, so that they finish before the air gets too arid. Desert plants might bloom for less than a week. Some tropical plants might bloom whenever they want to because they do not understand the concept of seasons, but they are not the prominent plants in our gardens. Therefore, flowers get scarce this time of year.

Besides the few perennials and annuals that bloom as long as the weather stays warm, there are not many plants that bloom reliably so late in summer. Belladonna lily, which is also known as naked lady, might be one of the flashiest, as its bright pink flowers bloom on top of bare stalks before the low basal foliage develops. It was actually dormant through the warmest part of summer.

Billowy and bold pampas grass flowers bloom this time of year, but are uncommon. The boldest type of pampas grass is too big and difficult to manage for home gardens. The smaller type has dingy tan flowers, and is so invasive and weedy that it is unavailable in nurseries. Those of us who have it in our gardens did not plant it. Other grasses with nice late flowers are not very colorful.

Russian sage has become one of the more popular late blooming perennials. More traditional Japanese anemone, goldenrod, lion’s tail and showy stonecrop all seem to have lost popularity over the years. Mexican blue sage should bloom best late in summer, but often finishes sooner than expected. Yarrow often blooms later than expected, until summer ends. Marigold, blanket flower and some sunflowers bloom until frost. Chrysanthemums, whether grown as annuals or perennials, are just beginning late in summer.

Flowers For Late Summer Bloom

80905thumbNo mater how much work we put into our roses to sustain bloom all through the season, and not matter how successful we are with that endeavor, the first spring bloom is always the best. Some roses continue to bloom in floriferous phases afterward, while others bloom sporadically but continually; but there is nothing like the first bloom phase. The last blooms are just waiting for autumn.

Of course, concentrating resources into early bloom is very sensible. That is why so many plants bloom only once in spring. It gives them time to get pollinated, develop seed and fruit structures, and finally disperse their seed or fruit structures, all before winter. Plants that bloom in summer or autumn are either from regions where winters are not too harsh, or where summers are harsher.

Because summer weather in most regions tends to be warmer and drier than spring weather, flowers that prefer to bloom in summer tend to be more prolific but smaller and less colorful. By this time of year, they are more reliant on wind for pollination rather than insects anyway. Therefore, they do not need to be big and colorful to attract pollinators, although some are fragrant just in case.

Sunflower, blanket flower, cone flower, zinnia, cosmos, delphinium, dahlia and of course rose, are some of the favorite flowers in the garden as well as for cutting in late summer and into autumn. Cut dahlia flowers should get their water changed daily so that they do not rot and smell bad so soon. Canna blooms about now, but does not last so well as cut flowers. Lily-of-the-Nile is finished.

Believe it or not, lemon bottlebrush is a delightful cut flower for those who are not allergic to it or repelled by the aromatic foliage. So are some of the showier eucalyptus, such as the red flowering gum, Eucalyptus ficifolia. Mexican blue sage that was cut back to the ground over winter blooms a bit in spring, takes a bit of time off through summer, and then starts to bloom as summer ends, ultimately blooming spectacularly early in autumn. A few other sages bloom as late, but few are good for cutting.

The Bad Seed

P80818KThis salvia would probably look badder without it. Yes, that’s badder and not better. I mean, if all these slightly unsightly seeded stems were cut back, then the even more unsightly deteriorating foliage below would be more prominent. When one looks at it that way, the bad seed suspended above does not seem all that bad.

It is doubtful that the ‘gardeners’ who ‘maintain’ this site put that much thought into it. They are, after all, the same who ‘maintain’ the firethorn that is pictured in this article from June 27 (The Wrong Plant In The Wrong Place https://tonytomeo.com/2018/06/27/horridculture-the-wrong-plant-in-the-wrong-place/ ). There were probably too busy botching something else to notice that this salvia is in need of botching as well.

There is some unpruned black sage nearby that displays similar but smaller seeded structures on more irregular and arching stems, rather than vertical stems that stand upright. They too are somewhat appealing in a weirdly sculptural sort of way. They might stay like that until winter, when they will likely get pruned back as they deteriorate in the weather.

Sunflowers are commonly left after bloom just because finches and other seed eating birds like them so much. They do not get cut down until the birds are finished with them. To many, this is the main reason for growing sunflowers.

Another excuse to be lazy about deadheading spent blooms is that many will provide seed that can be collected for the next season, or merely allowed to self sow and naturalize. Leaving open pollinated vegetables out to go to seed is a common practice. For example, the last few radishes to be pulled might just be left to bolt, bloom and go to seed. Cosmos tends to throw its seed whether we want it to or not.