Bougainvillea is profuse and vividly colorful.

No other bloom is comparable to that of bougainvillea. It is often profuse enough to nearly obscure the foliage. The color is remarkably vibrant. Magenta is the most popular color. Purple might be the second most popular color. Other cultivars bloom in delightfully rich hues of pink, red, orange, yellow and white. Some bloom with double flowers. A few dwarf cultivars have variegated foliage.

Bougainvillea is a thorny vine that leans on its support, rather than cling to it. Like climbing roses, it must be tied or woven into trellises. Larger cultivars can mix with the branches of trees and big shrubs to eventually reach more than thirty feet high. Many cultivars stay much lower. Some grow slowly, and do not get more than three feet tall. The lush foliage is evergreen with regular watering.

However, bougainvillea does not want too much water, and actually prefers to get a a bit dry between regular irrigation. Excessive irrigation may promote vegetative growth while inhibiting bloom. Excessive fertilizer does the same. Sunny and warm exposure promotes fuller bloom. In late spring, the first and most profuse of perhaps a few bloom phases can continue for more than a month.

Woody Vines Need Constant Attention

Many woody vines have no limits.

Grapevines that were not pruned aggressively enough last winter are tangled messes by now. Many grapevines that were pruned properly are tangled messes as well. That is their nature. Woody vines like grapevines grow rapidly and vigorously. They rely on other plants for support, and do what they must to get to the top. Woody vines are not concerned about the plants that support them.

Woody vines climb structures also. Some cling to stucco and siding with aerial roots or modified tendrils (holdfast discs), that ruin paint and promote decay. Woody vines with twining stems wrap around posts and beams, and then crush them as they grow. All sorts of vines can dislodge shingles, roof tiles, gutters, downspouts or window screens. Some sneak into basement or attic vents.

Even relatively docile woody vines can get out of control fast. Star jasmine performs well as ground cover, but can climb more than twenty feet up trees if neglected long enough. Pink jasmine, lilac vine and Carolina jessamine are tame enough for lattice, but get overgrown on top if not pruned down. American wisteria is much smaller than Chinese wisteria, but can still strangle small shrubs.

Woody vines are certainly worth growing. Chinese wisteria, autumn clematis, honeysuckle, bougainvilleas and various trumpet vines all have their attributes. They just require diligent maintenance and serious commitment. Most need more than just winter pruning. Some of the more vigorous sorts may need specialized pruning a few times annually. They also need serious accommodation.

Trellises and supportive structures must be resilient to the destructive forces of particular woody vines. For example, Chinese wisteria deserves a trellis or arbor of posts and lumber that its heavy vines will not crush. Boston ivy can climb bare concrete retaining walls, but must not attach to painted or wooden surfaces. No vines should climb on roofs, chimneys, vents, gutters or utility cables.

Just as importantly, woody vines require enough room to grow without crowding or climbing into trees or other plants.

Covering New Ground Or Old With Groundcover

Mock strawberry covers shallowly but densely.

As the simple name implies, ‘groundcover’ covers the ground. Groundcover plants stay lower than shrubbery, and function something like mulch. They insulate shallow roots of other plants, inhibit weeds, and some groundcovers inhibit erosion. Besides all their utilitarian functions, they provide appealing foliage, and some bloom nicely.

Lawn is probably the most common groundcover, and is also the most useful; but that is an entirely different and involved topic! Other groundcover plants are spreading perennials, plants with sprawling stems, or vines grown without support. Most are evergreen, since defoliated plants do not cover much of anything too well.

Gazanias and iceplants are popular perennial groundcovers. Their old stems tend to die out and decompose as efficiently as new stems pile up over them, which is why they do not get too deep. Gazanias can eventually get bald spots that need to be patched with new plants, or ‘plugged.’

(The debris from pruning the edges of easily rooted perennial groundcovers can be processed into cuttings known as ‘plugs’, which can go directly into bald spots. Plugs can be taken from dense spots if no edging is necessary. They should be watered regularly, or plugged in autumn to take advantage of rain while roots develop.)

Groundcover forms of ceanothus (wild lilac), juniper and contoneaster are really shrubs that extend their stems more horizontally than vertically. Honeysuckle and both Algerian and English ivies are vines that spread over the ground until they find something to climb. Their stems root into the ground wherever they need to.

Since most groundcover plants are naturally understory plants that grow below larger plants, many tolerate considerable shade. Periwinkle and the ivies are remarkably happy in partial shade. However, vines, particularly the ivies, will climb walls and trees for more sunlight if they get the chance.

Many of the perennial groundcovers and some of the vines are neater if mown or cut low annually. Periwinkle does not need to be mown, but can get rather unkempt before new growth overwhelms the old through winter. Mowing eliminates the old stems, and makes the new growth fluffier. Dwarf periwinkle stays too low to mow.

Dago Wisteria

All this bloom will eventually be fruit.

My colleague down south and I have completely different gardening style. He is a renowned landscape designer, so his home garden is as elaborate as the landscapes he designs for his clients. I am primarily a farmer of horticultural commodities, so my home garden is very strictly utilitarian, with few items that are grown just because they are pretty.

My colleague’s garden is outfitted with a very well built pergola over the patio at the rear of the home. Six common Chinese wisteria were installed to climb the six supporting post and sprawl above. Their cascading spring bloom is both spectacular and alluringly fragrant.

Of course, when I saw that pergola while the wisteria were still young, I thought that it would be ideal for Dago wisteria, which most of us know simply as grapes. They climb like Chinese wisteria. They bloom with somewhat pendulous floral trusses that . . . sort of resemble wisteria bloom. Although they lack color and fragrance, they provide an abundance of fruit.

Now I get to work with some real Dago wisteria. It was planted years ago by someone who did not stay to maintain it. It got rather overgrown and gnarly before I pruned it into submission. Without a pergola, I extended vines from the rail fence that the main vines climb, over to a banister on the upper floor of an adjacent building. It works something like a pergola.

Because I do not know what cultivar of grape the vine is, I do not know what pruning technique it prefers. I happened to leave long canes last winter, just because they reached the banister on the opposite side so well. Now, the bloom is so profuse that I am concerned about the weight of the subsequent fruit pulling the rail fence over!

Horridculture – Fences

This is not exactly visually appealing.

Fences are necessary. They contain children, dogs and minor livestock. They exclude deer, cattle and others who are unwanted within an enclosed space. Some obscure unwanted scenery. However, even the more ornate sorts are more functional than aesthetically appealing.

That is why hedges are popularly grown to obscure fences that obscure outside scenery. Climbing vines take up less space than hedges, but are likely to damage the fences that they are intended to obscure.

Where I lived in town, the garden in back was surrounded by fences. I loathed them. I grew a grapevine on one. Another one was outfitted with a trellis of twine for pole beans to climb. Tall zonal geraniums obscured at least the lower half of the fence behind the laundry yard. I would have preferred no fences at all.

There were no children or dogs to contain. Nor were there cattle or deer to exclude. Except for the laundry and trash yards, there was no unwanted scenery to obscure. Nonetheless, the neighbors wanted fences, probably because they all believed that backyards should be fenced. It was just how it had always been.

Some urban fences are more like high and solidly constructed walls. Batons cover the seams between planks. Where local ordinance limits the height of fences, lattice is commonly added on top to (sort of) lawfully increase height. It is difficult to grow much on the shady north side of such tall fences.

I am fortunate that I do not work with many fences anymore. However, an area at work is surrounded by cyclone fences. It is necessary and practical, but would be very unappealing around landscape situations. I put pole beans on one, and two grape vines on another. If I must contend with them, I may as well take advantage of them.

Horridculture – Major Improvement

A bit of Boston ivy adds a bit of texture and color to the stone wall.

My rant for this week is that I was deprived of my rant. I went to a nearby landscape that had been trashed by the so-called ‘gardeners’ for many years, only to find some unexpected and major improvements. I do not know what happened. Although it will take some time for the landscape to recover from the prior damage, it is already starting to function as intended.

It is obvious that the landscape was very well designed. Although I know very little about design, I know what is horticulturally correct. The designer selected species that are very appropriate for every application, even though none were particularly trendy at the time. Those who were hired to maintain the landscape only interfered with its intended development.

I noticed several improvements, but got pictures of only two features that bothered me the most prior to this season.

Obviously, the landscape designer intended the trailing rosemary in the picture above to cascade over the stone retaining wall, not so much to obscure the appealing stonework, but to break up its expansiveness. Obviously, the Boston ivy was intended to climb up from below to do a bit more of the same, and provide a bit of color in autumn, without overwhelming the rosemary.

Until recently, the so-called ‘gardeners’ had shorn the Boston ivy into useless little globs at the base of the wall. If it crept onto the wall, they were sure to remove it just as it was starting to exhibit color for autumn. The rosemary was never allowed to hang over the edge, and typically got shorn just as it was beginning a bloom phase.

Now, the Boston ivy is allowed to climb the wall somewhat. I suspect that it will be partly removed through the year, just so that it can provide a bit of color by autumn, but without getting too overgrown. Also, the formerly shorn edge of the rosemary is beginning to take on a natural form, and will likely start to cascade through summer, hopefully with occasional thinning.

What bothered me even more than the glaringly bare wall was how this pair of flowering crabapples in the picture below got hacked back annually just as the flower buds were beginning to show the slightest bit of color. Seriously! Every little twig that could have bloomed was removed. The so-called ‘gardeners’ were weirdly punctual about this.

Well, the trees got pruned a bit earlier last winter. What I did not bother to notice earlier was that much of the unsightly stems that had been disfigured by what the so-called ‘gardeners’ did to them were pruned back to healthier growth, while much of the blooming stems were left intact to bloom now! All the damage can not be repaired in one season, but this a great start.

Someone is putting serious effort into renovating these flowering crabbaple trees.


Blank Slate

This tank could use some greenery . . . or maybe not.

The scrub palm incident should have reminded me that there is such a thing as too much of good thing. By the way, I do intend to grow every single seedling that germinates and somehow find homes for them all. I suspect that almost all will live in my own garden, but at least I know they will live in a good home. I have grown surpluses before, and I actually plan to do it again.

For examples, that big herd of cedar seedlings that was partly reassigned into landscapes is just too numerous for all seedlings to be accommodated. Most of what remains will get canned to be installed into landscapes later. Since we planted about as many as we possibly can here, most will likely go to Los Angeles, and installed onto embankments of the Santa Monica Freeway.

That is too many cedars; but I just can not bear to discard them as I should. Nor can I leave them to grow into a crowded and likely rat infested grove. They should be happy in Los Angeles.

Anyway, I was asked to grow a few copies of Boston ivy for a pair of concrete columns that support a pedestrian bridge. Two specimens were already planted on two other concrete columns of the same pedestrian bridge, from which English ivy had been removed. Two other specimens grow on a concrete retaining wall from which Algerian ivy gets removed ahead of its advance.

I should have just plugged a few cuttings into a can, and then separated them and plugged them directly into the landscape as they rooted. Instead, I plugged cuttings into a flat. Well, I could not just plug a few, and leave the rest of the flat empty. I filled an entire flat with a hundred cuttings. I expected a high mortality rate, but alas, almost all of the cuttings are doing quite well.

Now we are finding all sorts of concrete retaining walls and other infrastructure where we can plant Boston ivy. We are also realizing that there is a difference between ‘can’ and ‘should’. As I was dumping greenwaste, I noticed how austere this big water tank looks. Boston ivy would really appreciate all that surface area! There is enough to plant all the way around the perimeter!

Then, I thought of all the reasons why clinging vines are not allowed onto water tanks. They deteriorate the paint, which allows the tanks to rust. They allow rodents to climb up to the top of the tank, which is really not a good place for rodents. They need maintenance, which is not justifiable for landscape features that serve no practical purpose. They need (ironically) watering.

If the tank were in a more prominent location where it should be obscured, it would be best to plant dense evergreen trees, such as cypress trees, around it. Such trees would be planted at a distance, to maintain reasonable clearance. Really though, the tank is in a secluded place, where not many of us see it. It needs no landscaping, so will remain as austere as it has always been.

But, what about the cyclone fence around the water tank? All those surplus grape vines could most certainly make good use of it as a trellis! Okay, I get it. It would take too much work, and there is too much potential from problems . . . rodents, maintenance, watering, damage to the fence, and half of all the grapes would be locked inside where only a few of us could get to them.

Fence or trellis?

Orange Clock Vine

It is time for orange flowers.

Since it rarely gets cold enough here to freeze the foliage and stems, clock vine, Thunbergia gregorii, provides very orange flowers throughout the year, and will bloom more profusely in summer. It is very similar to the more traditional black-eyed Susan vine, but the flowers lack the prominent black throats. Relative to most vines, orange clock vines is rather docile. The wiry vines are happy to climb to the height of first floor eaves, but do not go much farther. Without support, the vines grow as small scale ground cover.

New plants prefer full sun exposure, even if they later choose to spread into partial shade as they grow. Shade inhibits bloom. Once established, orange clock vine does not need much water, and can actually survive in abandoned landscapes. Overgrown or neglected vines can get weedy in spots, especially if not regularly watered. Fortunately, they are easily renovated by severe pruning at the end of winter. Even if pruned almost to the ground, vigorous vines regenerate very efficiently.

Keep Vegetation Clear From Chimneys

51028thumbFireplaces simply are not what they used to be. Building regulations in many municipalities do not allow for the construction of new fireplaces, except only for pellet stoves. Fireplaces that get damaged by earthquakes are commonly removed instead of repaired. Now that urban sprawl has replaced so many of the rural areas and defunct orchards, firewood is more expensive, even if purchased from a tree service. When a tree needs to be cut down, no one seems to have the time to cut and split the wood.

Modern heating systems are so much more reliable, efficient and just plain easy. Their fuel can actually be less expensive than firewood, and is not nearly as polluting. There is no smoke to offend the neighbors. There are no potentially dangerous sparks. There is no dirty chimney that needs to be cleaned. There is no need for firewood occupying space in the garden. Yet, with all the advantages of other heating systems, many of who still have fireplaces like to use them now that the weather is getting cool.

Because so much heat and a few sparks go out through the chimney, it is extremely important to keep trees and vines away from the top of the chimney. Cypress, pines, cedars, large junipers, eucalypti and fan palms that are not groomed of their dried old leaves are very combustible. Vines like wisteria, bougainvillea, creeping fig and Boston ivy are not unusually combustible, but have a sneaky way of overwhelming chimneys and accumulating debris (and sometimes rat or bird nests!). Any vegetation will be combustible if it gets hot enough. Sparks from burning foliage above can easily ignite old fashioned cedar shingles.

Trees should also be pruned away from roofs, gutters, fences and anything else that can be damaged by the abrasive motion of the stems and foliage in the wind. Stems of deciduous trees lose weight as they defoliate, and may even lift off of roofs that they had been leaning onto just a few weeks ago, but should be pruned accordingly anyway. Branches that have been leaning on a roof for quite a while may have accumulated a bit more debris than would be expected. Gutters and downspouts should be cleared of debris before the rain starts, and may need to be cleared again later where deciduous trees fill them up through autumn and winter.

Horridculture – Clinging Vines

P91113Ivy often climbs into trees, buildings and all sorts of other situations where it becomes problematic. It might have been planted intentionally. It might have grown from seed left by birds. When it gets into trouble, we can easily blame it on the ivy. Even that which was planted was intended to be mere ground cover. It only climbs out of control because that is what ivy does.


This Boston ivy that . . . ‘someone’ planted almost a year ago was actually expected to climb. That is what Boston ivy does. Even if it would be willing to grow as a ground cover, it would not work well as such because it is deciduous. As a climber, it covers freeway sound walls and any associated graffiti with vibrant green foliage that turns fiery orange and red this time of year.

The problem with it is that there are not many practical applications for it. Yes, it does well on freeway sound walls. It also does well on concrete parking structures, where it can not reach painted or wooden surfaces. There are a few unpainted reinforced concrete building out there that it would work nicely on, as long as it gets trimmed around windows, doorways and roofs.

It has no business on painted wooden surfaces, or even stucco. It clings with these weird ‘suction discs’ that never let go! (They do not really use suction, but an adhesive instead.) You can see a few to the right in this picture below. When vines get pruned back every few years, the suction discs remain attached. Although not a problem for concrete, they promote rot in wood.P91113+

What concerns me with the Boston ivy in these pictures is that it grew to the top of the pillars that they were planted on in less than a year. Even if they get pruned down this winter, they will grow farther next year, and will reach the wooden bridge above. It will be a lot of work to keep them pruned back from the bridge.

As you can see I the picture below, Boston ivy is quite pretty on the concrete. Fall color is delayed this year. P91113++