Woody Vines Need Constant Attention

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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.

Two Birds With Many Stones

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Gravel and stone function like mulch.

Fads are not necessarily bad ideas. Some evolve out of good ideas. Others are recycled old ideas that worked. The current popularity of stone, gravel and artificial ‘dry creek beds’ is probably the result of the drought. Yet, they were becoming popular before the drought. This is not their first time around either. They were popular through the 1970s and the 1950s as well.

Stone and gravel obviously do not need to be watered. Therefore, more area occupied by stone, gravel or dry creek beds equates to less area occupied by plants that want water. Such areas are not as useful as pavement or decking, but are more appealing where space does not need to be useful, and work nicely where the ground it sloped too much for pavement.

Stone around the trunks of mature trees works like an insulating mulch so that lawn grass and groundcover plants can be kept at a safe distance. Otherwise, the water needed to sustain the grass or plants against trunks can cause root or trunk rot. However, stone should not be piled so deeply that it holds moisture or interferes with aeration.

Stone is actually better than mulch in some situations. It does not decay. Stones and larger gravel are not likely to be blown or raked away, although small gravel can be difficult to separate from debris while raking. Since stone does not need to be replenished, groundcloth can be installed beneath it to prevent weeds from growing through.

Artificial dry creek beds do not need to be completely dry all the time. They can actually improve drainage in low spots that get saturated during rain. Stone on groundcloth drains better than soil or plants do. Artificial creek beds that are only ornamental should stay in low spots anyway. They look even more unnatural in high spots that water would not naturally drain to.

A few plants can go a long way in larger areas of stone or gravel, and particularly in artificial dry creek beds. If the stone is done properly and is appealing enough, the plants merely add a bit of color, form and texture, without completely obscuring the stone. Drought tolerant plants are of course more appropriate if the intention of stone is to conserve water.

Collecting Seed For Another Season

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From one year to the next.

Seed that is available in hardware stores and nurseries came from somewhere. Plants just like those that such seed grows into produced it. Someone, or many someones, collected all that seed to make it available to others. Similarly, several plants in our own gardens produce seed. Anyone who is interested in collecting seed to grow more of the same plants could make good use of it.

After bloom, most flowers deteriorate and disappear into the landscape. Some leave behind desirable developing fruits or vegetables. Many of the flashiest flowers are too extensively hybridized to produce seed. Many produce some sort of seed structure that typically gets removed, or ‘deadheaded’. This diverts resources from seed production to subsequent bloom or vegetative growth.

If not removed, such seed structures can mature to produce viable seed. Those who enjoy collecting seed often intentionally leave a few seed structures for that purpose, instead of deadheading completely. For plants with long bloom seasons, this technique should involve the latest blooms. The same applies to vegetables that normally do not mature prior to harvest, like summer squash.

Such seed or fruiting structures, including vegetables, must be completely mature before collecting ripened seed from them.

Sunflower, cosmos, calendula, marigold, campion, morning glory, columbine, hollyhock and snapdragon are some of the easiest flowers for collecting seed from. California poppy, alyssum, phlox, and several other annuals are happy to self sow their seed, although collecting seed from them is not so easy. Nasturtium and honesty (money plant) seed is easy to collect, but self sows as well.

Collecting seed is limited only by practicality. Some plants, particularly hybrids and exotics (which are not native and may lack pollinators), produce no viable seed. Extensively bred varieties are likely to produce progeny that are more similar to the basic species than the parent. Once collected, some seed need special treatment in order to germinate. All seed should be sown in season.

California Native Plants Exemplify Diversity

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Redwoods are the grandest native trees.

California native plants are logical options for the gardens and landscapes of California. It is only natural. They are already happy with the climates and soils here. They do not need to adapt quite as much as plants from other regions and climates do. After all, they lived here long before anyone else was here to water and maintain them.

Unfortunately, it is not that easy. California is a very diverse place. There are more climates here than there are within many other states combined, over a much larger area. Plants that are native to the Mojave Desert would not be happy in a rainforest of the Siskiyou Mountains. Coastal plants would be no happier high in the Sierra Nevada.

Within reason, California native plants for landscapes and home gardens should be either locally native, or native to similar climates. Plants from very different climates within California are about as exotic as plants from other continents. Just like foreign exotic plants, they may require special accommodation, such as irrigation, to survive here.

All plants need irrigation when first installed. Irrigation can be slightly complicated for plants that are native to climates with long and dry summers. They certainly need irrigation until they disperse their roots. However, a bit too much can rot their roots. California native plants can be sensitive like that. After all, they do not expect to be moist through summer.

Then, once established, many California native plants do not want frequent irrigation. Many want none at all. Chaparral plants like oak, manzanita, toyon, ceanothus and coyote brush tend to rot with too much watering. Plants that are native to riparian or coastal regions, like redwood, bigleaf maple, willow, cottonwood, elderberry and ferns, tolerate more irrigation.

Most California native plants that are from chaparral or desert climates do not perform well within the confinement of pots or planters. They prefer to disperse roots very extensively and directly into the soil, just like they do in the wild. Once established, they do not transplant easily.

Ponds Cannot Conserve Water

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Aquatic plants provide shelter for goldfish who eat mosquitoes.

During a drought, there really is no way to use less water in a garden pond. Aquatic plants can not survive without adequate water; not to mention fish! Pumps that circulate water must stay submerged to operate properly, and to not get damaged by operating without water. Some degree of water needs to be added regularly to compensate for evaporation.

Water does not evaporate from below the surface of the water. Therefore, depth is irrelevant to water loss. The area of the surface of the water is more important. Sunlight and wind accelerate evaporation. So do fountains or pumps that broadcast water through the air for circulation. Aquatic plants that stand above the surface of the water lose water to evaporation from foliar surfaces.

Yet, most of us who enjoy gardening cannot resist growing aquatic plants if a pond is available. Not only do they provide distinctive foliage and bloom, they also provide shelter for goldfish or minnows that control mosquitoes. They keep water clearer by competing with algae.

Submerged aquatic plants, like anacharis, do everything in the water. Some do not even need soil to root into. Because they do not come above the surface of the water, they do not affect evaporation. None of the floating plants, like water hyacinth, water lettuce and duck weed, have any use for soil either, although some of the leafiest sorts can accelerate evaporation.

Water lilies and lotus are emergent aquatic plants, which naturally live in mud on the bottom of ponds, but develop foliage and flowers that emerge and float on the surface. Although they have the potential to affect evaporation, most are more likely to inhibit evaporation by keeping water shaded. In garden ponds, they must be potted, and should be under at least a foot of water.

Relative to other aquatic plants, bog plants such as cattails, aquatic cannnas, and blue or yellow flag iris consume the most water from saturated soil at or just below the surface of a pond. They produce the most foliage that stands well above the water. Like water lilies and lotus, bog plants need to be potted, but with the tops of their soil barely below the surface of the water.

Pots should be low and wide, and obviously do not need drainage holes. Unnecessary holes only spill a bit of soil, and allow roots to escape and grab onto the bottom of a pond. Good old fashioned soil (yes, dirt from the garden) is fine. Good quality potting soil merely floats away.

Nursery Cans Are Only Temporary

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Nursery cans are not permanent pots.

Garden enthusiasts would understand the temporary nature of nursery cans better if they knew more about how plants grow in nurseries. Few plants actually grow in the retail nurseries that market them. They grow in production nurseries, where efficiency is a priority. Nursery cans, which retailers and consumers refer to as ‘pots’, are the most efficient means with which to contain the crops.

Most nursery cans are thin black vinyl. While plants are small, crowded ‘can to can’ arrangement shades the black vinyl so that it does not get too hot from sunlight exposure. Those on the western and southern edges of a crop might get shade from a temporary row of empty cans or a plank leaned against them. As plants mature and need more space, their growing foliage shades the vinyl.

As plants become marketable, they go from production nurseries to retail and wholesale nurseries. From there, they go to new landscapes and home gardens. Only then do they finally escape the nursery cans that they grew up in, to disperse their roots into real soil. The nursery cans have finished their job. Plants can not live in them forever, even if they continue to live in other types of pots.

Nursery cans are efficient, but not necessarily comfortable. By the time they are marketable, the plants that they contain are generally about as big as they can get within their cans. If they get any bigger, their roots will be crowded. If too exposed to sunshine, the black vinyl gets hot enough to cook the roots within. Plants prefer to be in the ground, or at least pots that are more comfortable.

Potted plants that will grow bigger should live in pots, planters or other containers that are bigger than the nursery cans that they grew in. Some will want even larger containers as they grow more later. Annuals and plants that will not grow much bigger are not so critical. However, all potted plants that will not shade their own pots appreciate containers that are better insulated than thin vinyl.

Clay pots, wooden planters and even concrete urns are as practical as they are appealing.

Pots Make More Out Of Less

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Half barrels are a bit elevated, and seem to show off their flowers better.

With conservation of water being so important right now, annuals are not a priority. Many of us are trying to use as little water as possible, and only to keep the more significant trees, shrubbery and perennials alive until winter. Lawn and annuals are usually the first to succumb, mainly because they use more water than anything else.

They are also somewhat expendable. Lawn is certainly expensive, but realistically, can be replaced as soon as water becomes available. Hopefully, new lawns will be more conservative with water, like they should have been since the last “drought” (and the one before that). Annuals are planted annually (duh), so they get replaced anyway.

Annuals as bedding plants over large areas were already somewhat passé before the last few dry winters. Even the more indulgent landscapes used annuals merely as relatively modest borders around or in front of more substantial, but less consumptive, perennials and shrubbery. Pots and planters are already more appropriate.

Some of the trendiest big pots are so ornate that they do not need flowers to provide more color. Besides, with a few striking perennials for colorful foliage or form, there is not much space left for annuals. What matters with annuals is that fewer in a pot can be flashier than more in the ground. Fewer annuals mean less water is required.

Elevated planters may not be as ornate, but display flashy annuals just as effectively. Petunia, million bells, lobelia and alyssum can cascade over the edges, to be colorful both on top and on the sides. Marigold, zinnia, celosia and any interesting foliar or sculptural perennials get a bit more height. It all helps to get a bit more out of less.

Pots and planters are not necessarily less work. They just need less water than larger beds, because they are smaller. Relative to their area, they actually need more water, and must be watered very regularly to sustain the confined roots within. Hanging pots need the most water. All confined plants benefit from fertilizer.

Culinary Herbs With Landscape Appeal

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Culinary herbs work well within landscapes.`

Vegetables grow mostly in designated vegetable gardens because they are not appealing enough for the rest of the landscape. Flowers for cutting might grow in designated cutting gardens, from which they are not missed after harvest. Culinary herbs can grow in herb gardens for the same reasons. Some might not be very pretty. After harvest, some might be too shabby for the landscape.

Of course, such perceptions are debatable. Home gardens are casual and customized. If Swiss chard, artichoke and other vegetables can grow in front yard landscapes, then culinary herbs can too. In fact, some already do. Rosemary, thyme, lavender and a few other culinary herbs happen to be popular for landscapes because they are so appealing and practical. There is a slight catch.

Culinary cultivars of herbs are distinct from landscape cultivars. Trailing rosemary is a landscape cultivar with sprawling growth that works well as a resilient ground cover. Another cultivar exhibits more sculptural upright growth. Both are well flavored. However, neither is as richly flavored as culinary cultivars of the same species. Yet, culinary cultivars are not so remarkable for landscaping.

Most of us are satisfied with landscape cultivars of rosemary for culinary application. Alternatively, culinary cultivars, which are rare in nurseries and landscapes, can adapt to landscape functions. Cultivars of culinary rosemary happen to make nice low and mounding hedging. Infrequent shearing or selective pruning does not constantly deprive it of too much of its more flavorful new foliage.

The same applies to several herbs that have both culinary and landscape applications. Compromise might be in order.

Incidentally, two culinary herbs, Grecian bay and bronze fennel, are presently quite trendy. Grecian bay or sweet bay (which is not California bay) is a very popular potted plant. In the ground, it can grow into a midsized tree. Bronze fennel is supposedly comparable to common fennel, but with sepia toned foliage. Chive, parsley and borage all work nicely with mixed perennials and annuals.

Covering New Ground Or Old With Groundcover

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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.

Sun Scald Happens Here Too

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Sun scald ruins otherwise good stems.

Those who enjoy gardening where winter weather is harsh likely know what sun scald is. It happens late in winter, if exposed bark warms enough to prematurely resume vascular activity during the day. Vascularly active tissue then succumbs to hard frost at night. Wintry sunlight is not sufficiently intense to scald bark; but the damage suggests otherwise. Glare from snow enhances exposure.

Of course, without hard frost or snow, this sort of sun scald is not a concern here. However, there is another sort of sun scald that happens during the warmth of summer. It truly is scald, caused by exposure to sunlight that is sufficiently intense to literally cook vascular tissue just below thin bark. Although induced by opposite extremes of seasonal weather, the damage is remarkably similar.

Since even deciduous trees are foliated during summer, most bark is safe from summertime sun scald. Bark becomes more exposed and susceptible if deprived of some of what shades it. That can easily happen if aggressive pruning diminishes the foliar canopy above. Removal of a nearby tree also eliminates significant shade. Painting an adjacent wall a light color can enhance glare.

White paint applied to the trunks of susceptible orchard trees reflects most of the damaging sunlight, but is too unsightly for landscape trees. Stubble of small twiggy stems can shade the trunks of some young trees until their canopies are broad enough to provide shade. Sun scald typically develops on southwestern and upper exposures that are more exposed to the most intense sunlight.

Maple, oak, ash, birch, flowering cherry, flowering crabapple, English walnut and almost all deciduous fruit trees are innately susceptible to sun scald. The interior stems of privet, holly and English laurel are more resilient to sun scald if exposed by major pruning during late winter rather than during summer. Although, with only a few exceptions, any thin bark can be susceptible to sun scald.

Foliage of many plants can be damaged by enhanced exposure too, but that is known as ‘scorch’, and is another topic.