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.

Summer Is Not For Planting

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New plants are less reliant on irrigation if installed at the beginning of the rainy season.

Autumn is the time for planting. Cooling weather slows plants down so that they do not mind disruption so much. Increasing rain (hopefully) keeps the soil evenly moist while roots slowly disperse. The combination of cooling weather, increasing rain and shorter days keeps plants well hydrated so they can slowly ease into spring.

Why is this important now? Well, it probably is not important. It merely demonstrates why this is not the best time for planting. Only a few warm season annuals and vegetables get planted this time of year. Seeds for certain autumn vegetables get sown now. Otherwise, more substantial plants should wait until autumn if possible.

Mid summer in some ways is the opposite of autumn. While the weather is warm, plants are too active to be bothered. Even minor disruption can be stressful. Soil moisture provided by irrigation is often too irregular and unreliable for dispersion of many new roots. There is less time to recover from stress during shorter nights.

Smaller plants and seeds survive summer planting better than larger plants do. Seeds need to disperse all new roots anyway, so they  will adapt to what they get. They certainly need regular watering, but are quite talented at putting their roots wherever the moisture goes. With a bit more time, smaller plants will do the same.

Larger plants have more difficulty with the planting process because they need to disperse so many more roots to get established. When they get planted, all their roots are initially confined to the volume of media (potting soil) that they were grown in. They are susceptible to whatever happens within  that limited volume.
For example, a small plant in a four inch wide pot is initially confined to less than sixty-four cubic inches of soil. It can double its soil volume to one hundred forty-four cubic inches by merely dispersing roots less than one inch laterally. A tree in a 24-inch wide box needs to disperse roots ten inches laterally to do the same!
It would seem that drought tolerant plants would be less susceptible to the stress of planting in summer.

However, they are more sensitive because they are so reliant on extensive root dispersion. Until they disperse their roots, they actually need to be watered as frequently as other plants do.

Summer Squash Excel All Summer

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Tender young summer squash are best.

Summer is for warm season vegetables like tomatoes, beans, corn, okra, and of course, summer squash. The name says it all. Summer squash are the sort of squash that develop and are ready for harvest through summertime. The season continues until the plants succumb to cooling autumn weather. The abundant squash fruits are best while young and tender, before they actually ripen.

Related winter squash grow through summer too. However, they ripen completely through the growing season before harvest in autumn. By the time they are ripe, their foliage will be succumbing to frost. They are much less perishable than summer squash are, so last for months if stored properly. Instead of producing abundant small fruits, winter squash plants produce only a few big fruits.

Summer squash plants can produce big fruits too, but at the expense of preferred tender juvenile fruits. They simply will not divert resources to new small fruits while concentrating their effort into a big fruit full of viable seed. After all, seed production is their priority. Regular harvest of juvenile fruits actually stimulates the production of more fruits. It forces the plants to redirect their resources.

There is certainly nothing wrong with summer squash fruits that have matured a bit more than they should. Stuffed zucchini is merely medium sized zucchini sliced in half lengthwise, hollowed out, stuffed and baked. Some people actually prefer to leave the last summer squash fruits of the season out in the garden to get as big as they can before frost. Such fruits are tough, but not too bad.

Common zucchini and its varieties are the most poplar of the summer squash. They are generally the most reliable and most productive. Crookneck squash are likely the second most popular of summer squash locally. They are slightly less productive, but provide variation of flavor. Pattypan squash have good flavor, and a slightly firmer texture that is an advantage for soups and freezing.

Other interesting varieties of summer squash are too numerous to list. Each exhibits its own distinct characteristics.

Know The Time To Conserve Water

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Automated irrigation is certainly not perfect.

In the wild, plants take water when it comes as rain. Native plants and plants that are from similar climates might be happy to get almost all of their water through winter, and almost none through summer. However, lawns and many other plants want some degree of water through summer. This is why most landscapes are irrigated.

Obviously, irrigation is unnatural. The main disadvantage is that it uses water that must be taken unnaturally from natural sources, which are often, and are presently depleted. The advantages (even during a drought) is that irrigation can be applied where needed, as needed, and when it is most appropriate.

Irrigation systems can be designed to deliver more water to plants that need it, and less water to those that are less consumptive. Watering by hose can of course be similarly tailored to the plants. The volume of water applied can be increased through warm and dry summer weather, and decreased or discontinued through winter.

Automated irrigation can be set to operate very early in the morning when no one is likely to be out in the landscape. The water gets used when the need for water in the home is minimal, so fluctuation in water pressure should not be a problem. If it operates early enough, irrigation can finish before anyone gets out to see it.

Furthermore, early morning also happens to be the best and most efficient time to apply water. Less water evaporates while the air is cooler and more humid. Therefore, more water soaks into the soil. Evapotranspiration (evaporation from foliage) is a bit subdued, so plants cycle through their own moisture a bit slower.

Many plants can just as easily be irrigated in the evening. This would allow even more time for water to soak in before the sun comes up. However, the problem for some plants and lawn is that moisture lingering on foliage all night long can promote the proliferation of all sorts of fungal diseases, including mildew.

Drip and similar irrigation is still the most efficient, simply because water is applied directly, with minimal evaporation. Broadcast irrigation from lawn sprinklers, especially fine mist, is much more susceptible to evaporation. Water evaporates as it gets sprayed through the air, and as it lingers on any wet surfaces.

Bronze Is The New Green

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Color like this needs no bloom.

Bronze foliage will never actually replace green foliage. Even if there were enough variety of plants with bronze foliage to do so, too much bronze would look dreary. Bronze is just another option for foliar color in landscapes with significant vegetation. It is distinct from simpler green, and contrasts nicely with gold, blue, gray and variegated foliage. Some bronze foliage is variegated too.

There is all sorts of bronze foliage. Some is brownish bronze. Some is reddish. The most popular bronze foliage is rather purplish. It can be evergreen or deciduous. Annuals, perennials, shrubs, vines, trees and houseplants can provide bronze foliage. Most plants that provide bronze foliage are variants of plants that also provide bloom or fruit. Some are common. Others are rather rare.

Bronze foliage is not an advantage to plants that produce it. The most efficient foliage is green. Gray or bluish foliage has the advantage of reflecting some of the harsh sunlight that could scald it in severe climates. Otherwise, foliage that is a color other than green reflects more of the useful sunlight than it should. Incidentally, dark foliage also absorbs more of the sunlight that can scald it.

This is why many bronze plants are noticeably less vigorous than their greener counterparts. Although it would not be an advantage in the wild, diminished vigor makes some bronze plants more adaptable to compact home gardens. For example, the brownish bronze ‘Summer Chocolate’ silk tree will not get half as high and wide as the common silk tree. It can fit nicely into a cozy atrium.

Cultivars of purple leaf plum, Japanese maple and Eastern redbud are more familiar complaisant bronze trees. ‘Ruby Lace’ honeylocust is still quite rare. Bronze shrubbery includes smokebush, Chinese fringe flower, elderberry, barberry and ninebark. New Zealand flax, canna, houseleek, ajuga, mondo grass and coral bells are popular bronze perennials. Cordyline is a larger perennial.

Bronze foliage adds a bit more color than typical green foliage. In the right situations, it is appealing bold.

Summer Vegetables Like Warming Weather

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Summer Vegetables Like Warming Weather

Tomato, pepper and eggplant plants should be out in the garden by now. They typically get planted only a few weeks after the last threat of frost, so that they can start to disperse their roots early. Growth above ground accelerates as the weather gets warmer. Fruit develops and ripens through summer.

These three types of vegetable plants get planted as seedlings for two main reasons. First, when they go into the garden, seedlings are bigger and more established than seeds that need to take time to grow are. Secondly, the cost of the few plants needed for an average garden is not much more than the cost of seeds.

Now, zucchini, melon and summer squash can be done either way. Not many plants are needed, so the expense of seedlings is minimal. However, seedlings are a bit more fragile than those of tomato, pepper and eggplant. Seeds grow so efficiently that they get established almost as readily as seedlings do, so are just as practical.

Regardless of how they get planted, the weather has been so odd this year that there has been only minimal advantage to planting seedlings and sowing seed on time. Tomato, pepper and eggplant plants that were planted early may not be much more mature than what could be planted now. Harvest will be delayed either way.

Bean, cucumber and corn all grow best from seed. Seedlings take more time to recover from transplant than seed take to germinate and grow. Besides, so many plants of each type are needed that seedlings would be expensive. A single package of seed is cheap and goes a long way, so is probably sufficient for an average garden.

Corn is one of those vegetables that produces on a rather tight schedule. Seed that gets sown at any particular time matures at the same rate, so that all the fruit finishes at about the same time. This is why corn gets sown in phases. If timed properly, a subsequent phase begins to produce as the preceding phase gets depleted.

Winter squash, including pumpkin, are similar to summer squash, although they are more tolerant of unusually cool spring weather. They too can either get planted as seedlings or sown as seed. They take their time to produce fruit that ripens by autumn, so have more time to catch up.

Hanging Planters Need Extra Attention

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Some plants cascade nicely from pots.

With few exceptions, plants dislike confinement of their roots. They prefer to be in the ground where they can disperse roots freely. Houseplants stay potted because of a lack of other soil inside. Some plants live in pots for portability. Some plants just happen to look good in pots. Plants in hanging planters conform to any combination of these and other reasons. They serve their purpose.

Most hanging planters are simple pots suspended by three wires, chains or strands of plastic, jointed at a hook or loop. The hook or loop hangs from a hook affixed to a ceiling, eave, rafter, beam or tree limb. Hanging baskets are pot-shaped mesh or metallic baskets outfitted with fibrous lining to contain the medium within. Small plants or cuttings can grow from holes cut through the lining.

Of course, hanging planters for houseplants are generally pots instead of baskets, which are too messy for inside. They are likely also outfitted with big saucers for drainage. Hanging planters just happen fit well into spaces that are not useful for much else, such as up near a ceiling in a corner. Many of the most popular houseplants just happen to cascade splendidly from hanging planters.

Portability is another advantage of potted plants. Hanging planters that contain frost sensitive plants outside can spend winter in sheltered situations. Orchids and epiphylums that are prominently displayed during bloom can return to less prominent spots when finished.

Hanging planters are popular mostly because some plants simply look better in them. Cascading houseplants like Boston fern, pothos and spider plant, might look a bit mundane on flat surfaces. Many low growing bedding plants are more impressive if suspended at eye level than they are in the ground. Some bedding plants and small perennials excel at cascading from hanging planters.

However, hanging planters are very different from the ground. Because of limited root dispersion, potted plants rely more on regular watering than those in the ground. Because they are exposed to open air, they dry out fast, so crave more water.

Everything Is Coming Up Roses

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Grafting combines good scions with understock.

When an individual rose shrub blooms with two distinct types of flowers, it seems to be doing a little extra. It provides the big, bold and strongly stemmed roses that it is grown for, along with daintier dark red roses. Eventually though, the small red roses become more abundant, and can crowd out the more desirable roses.

Almost all of the older roses that are grown for cutting are grafted. This means that the stems that provide such excellent flowers above ground are attached to genetically different roots. When such plants were young, the graft union was more obvious, where the canes branched out from the single stem just above the roots.

The stems above the graft union are known as the ‘scion’. The roots below are known as the ‘understock’ or ‘rootstock’. The two are grafted together because the scion blooms so well, and the understock develops stronger and more efficient roots. Scions are not expected to grow roots any more than understock is expected to bloom.

Adventitious stems that develop from the understock below the graft union are known as ‘suckers’, probably because they suck resources that should go the scion. They should be removed as soon as they get noticed, before they can dominate the scion. They become more difficult to remove as they mature.

If possible, fresh new suckers should get broken off from their origin instead of simply pruned away. It sounds violent, but is actually more effective. Stubs left from pruning are much more likely to develop more suckers later. Suckers that get pruned back repeatedly can develop into significant burls.

Old rose shrubs that were planted with an abundance of organic soil amendments tend to sink into the ground as the soil amendments decompose. If a graft union gets buried, it can be difficult to distinguish between suckers and good canes that develop above the graft union.

‘Tree’ roses have two graft unions. The branched scion on top is grafted onto a straight stem of a different variety. The straight stem is grafted onto the understock at ground level. The trendy carpet roses and some other modern roses are not grafted, so will not develop suckers.