Too much in the garden may be going to pot.

Container gardenin is overrated.

The class of 1985 epitomized the ‘Decade of Decadence’ with the raddest of styles in the wildest of colors. My generation is perhaps more familiar than any other with the pursuit of senseless fads and trends. Now that it is about a quarter of a century later, many of us continue such indulgences in our gardens.

Container gardening has become a fad that, despite its practicality for all sorts of applications, has become so common that it actually makes gardening more work than it should be. Modern homes are built with expansive porches and walkways that are designed to accommodate large urns and other planters, instead of more modest and proportionate porches and walkways that leave more space for planting things in the ground around them. Runoff from the planters stains pavement and rots decking. Besides, all the clutter of planters looks like a garage sale.

For balconies, roof gardens or wherever exposed soil is otherwise unavailable, container gardening may be the only option. Containers also help with plants that need to be moved to sheltered spots during frost. However, few plants are as happy in containers as they would be in the ground. Contrary to popular belief, it is better to amend inferior soil in the ground than to grow plants in potting soil within pots.

Where pots or other containers are necessary, they should either be shaded, or otherwise insulated from the heat of the sun. The black vinyl cans that plants arrive from the nursery in are not only unappealing, but can get warm enough in the sun to roast roots. Yet, they are both obscured and shaded simply by getting placed within slightly larger urns or planters.

Other thin plastic pots can transfer heat like black vinyl, but tend to be cooler because they are most often lighter colors that absorb less heat from sunlight. Thicker materials, such as terracotta, are better insulated. Roots prefer the porosity of unglazed pots, although some glazed pots can stay cooler. Plants within containers are often able to provide their own shade by cascading out over the edges, or spreading out above.

Yet, more substantial plants that provide more substantial shade still need to be complaisant to confinement. Plants that need to disperse their roots will never be comfortable in containers. Neither will plants that are not conducive to pruning, but want to grow into large shrubs or trees.

Not All Plants Like Fads.

Ornate pots and planters can be as decorative as the plants within them, and provide extra accommodation for more plants.

Like so many fads too often are, container gardening is overrated, and is actually contrary to the currently most faddish of fads; sustainability. Plants in containers need more regular watering than those that can disperse their roots more extensively into the ground. Those that are so indulged also want fertilizer to be applied more regularly, but are more likely to be damaged if fertilized too generously. Because confinement is stressful, plants in containers are innately more susceptible to disease and pests. Some plants need more pruning for confinement.

Then there are the problems with the containers. If exposed to sunlight, thin plastic containers get warm enough to cook roots within. Pots that do not drain adequately or that sit in their own drainage basins can stay saturated enough to kill roots. Water in drainage basins allows mosquitoes to proliferate. Seepage from large pots can rot decks and stain pavement. Self watering containers work nicely for houseplants (if used properly!), but lack drainage, so can not be used out where they are exposed to rain.

The advantages to container gardening are actually quite limited. Containers are obviously needed for houseplants, and where exposed soil is not available, like on balconies. They are also convenient for plants that want better soil than they can get in the garden, especially if the rest of the garden is responsibly landscaped with sustainably undemanding plants that do not require soil amendment or regular watering. Frost sensitive plants can be moved easily to sheltered locations if contained. Flashy plants like orchids and tuberous begonias that get displayed prominently while blooming can be concealed while not so impressive.

Of course there are many pendulous plants like Boston fern, spider plant, string or pearls and burro’s tail that really are at their best in hanging pots. It is also hard to deny that there are all sorts of artsy containers, like colorfully glazed pots and sculptural concrete urns, which are appealing enough to justify growing plants in them, even if just to show off the fun containers. Bonsai requires containers, but that is another big topic!

Some Plants Can Go To Pot.

What ever happened to those poinsettias and cyclamen from last Christmas?

Chrysanthemums, hydrangeas, azaleas, callas, kalanchoes and miniature roses can not really be as happy as they seem to be while in full bloom at the florist counter. Then there are all the seasonal blooming plants like Easter lilies and poinsettias. Wrapped in undraining mylar, often with ribbons and bows, they are actually quite humiliated.

All are forced to bloom in artificial greenhouse environments that are nothing like the home environments that they ultimately go to. As they finish bloom, most get retired directly to the garden where many are unable to adapt quickly and efficiently enough to survive for long. Many do not make it that far, but get sent to the compost or the trash by those who prefer to not prolong their agony.

These potted plants (which are actually known as ‘pot plants’ in the horticultural industries) are not like houseplants, since they are not actually expected to survive for long in the home. They are only expected to perform for a limited time while in bloom.

Adapting to the home environment is not the difficult part. Most potted plants can manage that for a while, but eventually want more sunlight. Hydrangeas, roses, Easter lilies and other deciduous plants also eventually want a cool winter for their dormancy. The problem is adapting to exposure to the sunlight and weather that these plants crave. Foliage can get scorched, frozen or desiccated.

As unsightly as plants can be during transition, most can eventually replace their greenhouse foliage with foliage that is adapted to their new environment in the garden if transitioned slowly and carefully. Large ‘forced’ flowers will eventually be shed or can be pruned off as they deteriorate. The more sensitive types of plants should be moved to a sheltered spot on a porch or in partial shade for a few months before being moved to more exposed spots. Once in the garden, they will want regular watering until their roots disperse.

Deciduous plants and bulbs can stay in the sheltered spot until they defoliate for winter. If put into their permanent location while dormant and bare, their new foliage that emerges in spring will be adapted to the new exposure.

Aloes, Christmas cactus and various other succulents are considerably more resilient and adaptable than the more common potted plants. Both rosemary and small olive trees that have become trendy during the past many years can likewise be adaptable if not kept in the home too long. Olive trees can stay potted indefinitely if pruned regularly, or can go into the garden where there is room to grow. Christmas trees are just as adaptable, but do not want to stay potted for long. Sadly though, most get much too big for home gardens.

Potted Plants Need Work Too

Most potted plants would prefer to be in the ground, . . . if possible.

Potted plants can be a problem any time of the year. Some want more water than get. Most get too much water or do not drain adequately. Large plants get constricted roots if pots are too small. The roots of some plants get cooked in exposed pots that collect too much heat from sunlight. Besides, too many pots just seem to be in the way in otherwise useful spaces on decks, patios and anywhere else trendsetting landscape designers want to put them.

Now that the weather is getting cool and rainy, potted plants are not as active as they were during warm weather. Many are dormant. Although few demand the attention that they got during warmer weather, plants still need to be tended to appropriately through autumn and winter.

Cool season annuals, which are also known as ‘winter’ annuals, should get groomed as long as they are performing in the garden, just like warm season annuals get groomed through summer. Deteriorating flowers should be plucked from pansy, viola, primrose, Iceland poppy, calendula, dianthus, stock, chrysanthemum and cyclamen because they can mildew and spread mildew to developing flowers and foliage. Unplucked cyclamen and calendula can develop seed which diverts resources from bloom.

Pots that are out in exposed areas will not need to be watered while they get enough water from rain. The problem is that many that do not drain adequately can get too much water from rain and stay saturated. Dormant and defoliated plants do not need much moisture at all. Even evergreen plants do not need as much as they do while active during warm weather, because cool and humid weather inhibits evapotranspiration (evaporation from foliar surfaces).

Potted plants under eaves also need less water while the weather is cool and humid, but need to be watered nonetheless because they are sheltered from rain. Plants in hanging pots typically drain and dry more efficiently, so probably want a bit more water. Even a few sheltered small plants in the ground may occasionally want to be watered during rainy weather if they do not extend enough roots where they can get moisture from rain beyond the sheltered area. Sheltered plants are actually the most likely to be neglected because watering does not seem so important when it is raining.

Not All Plants Like Fads.

Ornate pots and planters can be as decorative as the plants within them, and provide extra accommodation for more plants.

Like so many fads too often are, container gardening is overrated, and is actually contrary to the currently most faddish of fads; sustainability. Plants in containers need more regular watering than those that can disperse their roots more extensively into the ground. Those that are so indulged also want fertilizer to be applied more regularly, but are more likely to be damaged if fertilized too generously. Because confinement is stressful, plants in containers are innately more susceptible to disease and pests. Some plants need more pruning for confinement.

Then there are the problems with the containers. If exposed to sunlight, thin plastic containers get warm enough to cook roots within. Pots that do not drain adequately or that sit in their own drainage basins can stay saturated enough to kill roots. Water in drainage basins allows mosquitoes to proliferate. Seepage from large pots can rot decks and stain pavement. Self watering containers work nicely for houseplants (if used properly!), but lack drainage, so can not be used out where they are exposed to rain.

The advantages to container gardening are actually quite limited. Containers are obviously needed for houseplants, and where exposed soil is not available, like on balconies. They are also convenient for plants that want better soil than they can get in the garden, especially if the rest of the garden is responsibly landscaped with sustainably undemanding plants that do not require soil amendment or regular watering. Frost sensitive plants can be moved easily to sheltered locations if contained. Flashy plants like orchids and tuberous begonias that get displayed prominently while blooming can be concealed while not so impressive.

Of course there are many pendulous plants like Boston fern, spider plant, string or pearls and burro’s tail that really are at their best in hanging pots. It is also hard to deny that there are all sorts of artsy containers, like colorfully glazed pots and sculptural concrete urns, which are appealing enough to justify growing plants in them, even if just to show off the fun containers. Bonsai requires containers, but that is another big topic!

Roots Prefer To Roam Freely

Some yuccas are unhappy in pots.

Roots are innately mysterious. They consume much of the resources that plants require. They stabilize the stems above them. Few plants can survive without them. Yet, roots are very secretive about their work. Almost all are invisibly subterranean. Consequently, they get minimal consideration. A lack of consideration is a root cause of many root problems. 

Every plant species has distinct environmental preferences. Some plants require full sun exposure. Others tolerate or prefer partial shade. Some are more discerning than others. Similarly, plants that naturally disperse their roots extensively dislike confinement of their root systems. Small plants and some riparian plants are more adaptable to confinement.

Annual bedding plants and many small perennials perform well within pots, planters and small spaces because they do not need to disperse their roots extensively. Some woody plants with fibrous root systems, such as azalea, boxwood and andromeda, can adapt to confinement also. Occasional pruning can keep them proportionate to their root volumes. 

Most of the popular succulents perform remarkably well in confinement. Some types that disperse their roots extensively if necessary will adapt to confinement by dispersing their roots only as far as they must. If they get all they need within a pot, they need not go any farther. However, succulents that are endemic to dry desert regions are not as adaptable. 

Desert plants can survive warm and dry summers because they disperse their roots very extensively. They can not do so within the confinement of pots and planters. This should not be a problem that systematic irrigation can not compensate for. Unfortunately though, these same plants are too susceptible to rot if their roots are damp during warm weather.

So, some plants that are the most resilient in the ground are the least resilient in pots. Of course, this is not an absolute rule. Yuccas from tropical and temperate climates perform well either in the ground or in pots. Those from desert climates are likely to rot in pots. In general, drought tolerance and container gardening are two fads that are not compatible. 

Planters Are Overrated But Functional

Some plants should always be confined.

Container gardening is overrated. The endemic soil here is not so bad that nothing will grow in it. What is now suburban gardens was formerly famously productive farmland! Soil amendments make the soil more comfortable to plants with more discriminating taste. Plants that are too discriminating are probably not worth accommodating. With few exceptions, planters are unnecessary.

Plants naturally want to disperse their roots into the soil. Drought tolerant plants disperse their roots even more extensively. That is how they find enough moisture to be drought tolerant. If deprived of such root dispersion, they are always reliant on watering. Plants prefer the insulation of soil too. Many types of planters can get uncomfortably cool in winter, and uncomfortably warm in summer.

Besides, planters clutter landscapes, and occupy space on hardscapes. Decks rot. Patios stain.

The main advantage of planters is their portability. Plants that are sensitive to frost can move to shelter before the weather gets too cool. Plants that are spectacular only while blooming can move for more prominent display during bloom. For those who have not settled into a permanent home, plants in planters are able to relocate. Planters on patios or decks can move about like furniture.

Houseplants obviously grow in planters because not many houses contain enough soil for them to live in. Houseplants can move about just like planters in the garden. That is helpful for those that need a better exposure for winter than they enjoy for the summer. Some might like to go into the garden during mild weather, or for a rinse in light rain. Cascading plants can hang from the ceiling.

Planters can effectively confine invasive plants as well. Montbretia is so invasive that some people will not grow it without containment. (Deadheading to prevent seed dispersion is important too.) Horseradish often grows in tubs for confinement, as well as to facilitate harvest. It is easier to dump the potting media from a planter, and separate the roots out, than to dig roots from the ground.

Potted Plants Need Work Too

Potted plants do not have much soil volume to work with.

Potted plants can be a problem any time of the year. Some want more water than get. Most get too much water or do not drain adequately. Large plants get constricted roots if pots are too small. The roots of some plants get cooked in exposed pots that collect too much heat from sunlight. Besides, too many pots just seem to be in the way in otherwise useful spaces on decks, patios and anywhere else trendsetting landscape designers want to put them.

Now that the weather is getting cool and rainy, potted plants are not as active as they were during warm weather. Many are dormant. Although few demand the attention that they got during warmer weather, plants still need to be tended to appropriately through autumn and winter.

Cool season annuals, which are also known as ‘winter’ annuals, should get groomed as long as they are performing in the garden, just like warm season annuals get groomed through summer. Deteriorating flowers should be plucked from pansy, viola, primrose, Iceland poppy, calendula, dianthus, stock, chrysanthemum and cyclamen because they can mildew and spread mildew to developing flowers and foliage. Unplucked cyclamen and calendula can develop seed which diverts resources from bloom.

Pots that are out in exposed areas will not need to be watered while they get enough water from rain. The problem is that many that do not drain adequately can get too much water from rain and stay saturated. Dormant and defoliated plants do not need much moisture at all. Even evergreen plants do not need as much as they do while active during warm weather, because cool and humid weather inhibits evapotranspiration (evaporation from foliar surfaces).

Potted plants under eaves also need less water while the weather is cool and humid, but need to be watered nonetheless because they are sheltered from rain. Plants in hanging pots typically drain and dry more efficiently, so probably want a bit more water. Even a few sheltered small plants in the ground may occasionally want to be watered during rainy weather if they do not extend enough roots where they can get moisture from rain beyond the sheltered area. Sheltered plants are actually the most likely to be neglected because watering does not seem so important when it is raining.

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.