Life was very different where I lived in town in the 1990s. I miss that neighborhood and my garden there very much. However, it was an urban neighborhood, only a few blocks from the interchange of Highway 17 and Highway 85. My neighbors had me build a small solar powered fountain adjacent to a patio of our apartment building to obscure the ambient urban noise. I thought it was a silly component of the landscape, but everyone else was fond of it. Well, sadly, I left that home and garden many years ago, and relocated to a quieter neighborhood a few miles away. Except for a few lights at night on distant hillsides, I can see no other households. I do not hear much more from them than I can see. Air traffic to and from Mineta is the most traffic that I notice, if I notice. In fact, the noisiest noise in my garden is from this creek that flows through it. I flows all day at night, so does not stop when the sun goes down. I can not unplug it. It gets louder during winter. Perhaps I should build another solar powered fountain to obscure the noise.
Rain is less abundant and less frequent now that winter has become spring. Humidity is decreasing. Temperatures are increasing. Moisture within both the soil and the air is less abundant than it had been. Irrigation that discontinued as the rainy season began should resume soon. Only supplemental watering compensates for the increasing lack of water.
Warmer and drier weather does more than simply deprive vegetation of natural moisture. It also accelerates new growth of formerly dormant or partially dormant vegetation. Such growth requires more moisture as it becomes less available. Increasing day lengths with intensifying sunlight enhance this need for watering. Although natural, it all seems ironic.
This recent need for watering is progressive. Rain still sometimes interrupts it, but will be less frequent as spring progresses. Rain will be very unlikely after later spring. Humidity will continue to decrease as temperatures continue to increase. Watering frequency and volume must increase accordingly. They might not begin to decrease until after summer.
Soil composition and texture also influence the increasing need for watering. Organically rich soils retain moisture more efficiently than sandy soils, for example. Gravely soils that drain well may necessitate frequent watering, even if less copious. Potted plants require frequent watering because they can not disperse roots. Hanging pots require even more.
Furthermore, different types of vegetation need different or specialized types of watering. Fibrous but shallow roots usually need frequent watering, even if they do not need much. Species with deep roots usually need watering less frequently. Some of them need more significant volumes of water than others. Some vegetation prefers only minimal watering.
With all these many variables, there are no simple formulas to determine watering rates. Manual irrigation is easiest to monitor, but is also tedious. Automated irrigation, although less tedious, requires more diligent monitoring. For any particular type of vegetation, soil should not remain too dry for too long. Also, vegetation should not exhibit any symptoms from desiccation.
Ferrum, which is abbreviated as “Fe”, is the chemical and element name of iron. It is apparently too abundant in this well water. Actually though, it is from the lining of the well. It accumulated because the pump has been inactive for so long. I am impressed that it functions at all after being idle for so long. I am concerned about the lining of the well, though. The hydrologic engineer tells me that I must superchlorinate the well to kill most of the iron oxidizing bacteria, and then flush the well by operating the pump for a long time. That all sounds like quite a bit of risky work. I do not like the concept of pouring something into a well that does not belong there. I am also concerned about what to do with the chlorinated water as it gets pumped out. I suppose that I could apply it to undesirable vegetation around the well. There will undoubtedly be a large volume of such water; but there is also a large amount of undesirable vegetation. I suppose that I could collect some or much of the water into an otherwise unusable tank to let the chlorine slowly volatilize from it. For now, until this superchlorination process begins, I suspect that this water is safe for irrigation. I do not mind if it leaves a temporary rusty residue that eventually rinses away. The water was even muckier before, and will get less mucky as more of it is used, so it could appear to be clean before superchlorination. Besides, I suspect that mucky water is less toxic to vegetation than superchlorinated water is. Because the rain stopped as suddenly as the rainy season began, and no rain is forecast for the next week, irrigation is now becoming a priority.
There are too many bridges to count here. Several roads and trails, and a historic narrow gauge railroad cross over two creeks and two streams within a relatively confined area. This particular suspension bridge is for a hiking trail that crosses over Zayante Creek at the downstream edge of its confluence with Bean Creek. Bean Creek, which is to the upper right in the picture below, flows through the farm on the outskirts of Scotts Valley. Zayante Creek, which is to the left in the picture below, flows through my neighborhood on the outskirts of Los Gatos. Ferndell Creek, which is just a stream from a nearby spring, also flows into this same confluence, but is not visible to the right of the picture below.
All of these creeks and streams sustain even more diverse ecosystems than those of the redwood forests above, and the chaparral pine forests a bit father above. Redwoods grow like weeds here. The redwood in the picture below is what is known as a ‘virgin’ because it was not harvested for lumber when most others were clear cut harvested to sustain development of the San Francisco Bay Area, and to rebuild San Francisco after the Great Earthquake and Fire in 1906. It was most likely rejected because it was too small to bother with at the time. Only a century later, it is massive! The cables that are now embedded into its bark formerly supported an older suspension that the newer bridge replaced many years ago. Although redwoods are not necessarily a riparian species, and can actually be resilient to drought, they do enjoy this abundance of moisture. The many other trees that inhabit these ecosystems with them grow very tall to compete for sunlight, and in some situations are excluded by their dense growth.
Some irrigation becomes temporarily obsolete through the rainy season.
Now that it has started to rain, what should be done with automatic watering systems? In almost all situations, automatic irrigation systems should be adjusted to accommodate for moisture provided by rain. If rain is sufficient to provide enough or too much water, irrigation can be discontinued until needed again when the rain stops a few months from now.
If the first few storms are discontinuous enough with warm and dry weather mixed in between, lawns and plants that want more substantial watering may need to be watered a few times until the rain becomes more reliable. However, because of cooler temperatures and shorter days, plants do not use nearly as much water as they did during the summer anyway, so do not need to be watered nearly as much as they were only a month or so ago.
Deciduous plants that are losing their leaves need the least moisture, since they can not lose any moisture through evapotranspiration (evaporation from foliar surfaces). The very few plants that bloom or even start to grow during winter use a little bit more water than those that really are dormant, but are still likely get all they need from rain even without getting watered.
Flowering annuals, particularly left over warm season annuals that continue blooming late, may get moldy with too much rain. Their flowers and some of their foliage can turn to mush until there is a break in the rain. Removal of damaged flowers and leaves slows the spread of the mold but does not cure it. Good air circulation among well spaced plants and in exposed areas helps inhibit mold. Regardless, moisture from abundant rain can eventually cause mold to be a problem.
In fact, the only plants that are not likely to get all the water that they need from rain are those that are in pots and planters under eaves or in the home as houseplants. Nonetheless, sheltered plants that are outside should still get much less water now than they do during the long and warm days of summer. These plants are either dormant or at least more sedate because of the shorter cooler days through winter. Houseplants may likewise use less water because the home environment is also cooler.
However, if the heating system of the home decreases humidity, some large houseplants may actually want a bit more water through winter! Humidity fluctuates most in older deficiently insulated homes that are heated by wood stoves or fireplaces; since these homes get humid without a fire burning, but then get much drier with a fire.
“Zeroscape” is a neologism that evolved from “xeriscape”. It was a mispronunciation that became a misspelling that became a real word. Ironically, it makes sense. It evolved with the misconception that a xeriscape requires no maintenance. Now, the two are different types of landscapes. A Zeroscape is pavement or gravel that requires zero maintenance.
A xeriscape is a landscape of xeric vegetation. Generally, such a landscape needs less maintenance than conventional landscapes. Nonetheless, some degree of maintenance is necessary. Furthermore, several xeric species require very specialized maintenance. Such specialized requirements may be more demanding than more familiar gardening.
The primary advantage of a xeriscape is that it needs less water than other landscapes. Some xeric species are native to Mediterranean climates. More are native to arid desert climates. Once established, they need minimal irrigation. Many xeric species get all the moisture they need from seasonal rainfall. Some can not tolerate much more than that.
Native species that grow wild can be surprisingly difficult to establish in home gardens. Some xeric species can be even more uncooperative. Cultivation within a garden is very different from natural conditions. In the wild, such species disperse roots proportionately as they grow from seed. In a garden, they begin with detrimentally confined root systems.
Even xeric vegetation within a xeriscape needs moisture while it disperses roots. A few may get enough through winter if they get into a garden early in autumn. Most prefer a bit of irrigation at least through their first year. The difficulty is that some can rot if irrigation is even slightly excessive. They are more susceptible to rot than species that are not xeric.
Maintenance of a xeriscape, is more challenging than demanding. That is because so many xeric species are from harsh desert ecosystems. They innately defend themselves from grazing wildlife. Consequently, cacti, agaves and yuccas are wickedly thorny and spiny. Several are potentially dangerous to handle. So are some euphorbs and acacias. They may not need maintenance often, but when they do, they do not make it at all easy.
Spring, in several regards, is like autumn in reverse, or vice versa. Bloom increases for spring but decreases for autumn. Foliage increases for spring but decreases for autumn. The two seasons are in opposition. In this chaparral climate, the rainy season that began last autumn ends now. Irrigation that became redundant then becomes necessary now.
Diminishing rain is not the only reason that irrigation becomes more important for spring. Spring weather also becomes warmer and more arid, or less humid. Warmth and aridity increase evaporation of moisture that rain deposited not long ago. Increasing day length, intensifying sunlight and warmth accelerate plant growth. Such growth consumes water.
This need for moisture is progressive, though. Vegetation certainly requires more water as the weather becomes warmer and drier. However, it does not yet require as much as it will require later during summer. By then, the weather will be even warmer and drier, and the days will be even longer. Irrigation should increase accordingly in regard to weather.
Unfortunately, there are no simple formulas to determine how much irrigation is needed. Some vegetation with shallow roots may require frequent but moderate irrigation. Some vegetation with deep roots may prefer less frequent but more copious irrigation. Rain is possible at any time. It can briefly interfere with the most efficient of irrigation schedules.
Soil also affects irrigation. Sandy soils drain efficiently, but do not retain much moisture. This may not be a problem for some species that tolerate occasionally dry soil. It may be more of a concern for species that prefer more regularly moist soil, though. Dense soils retain more moisture, but do not drain as efficiently. Soil amendments can improve soils.
Manual irrigation is easier to monitor than automated irrigation, but can be tedious. That is why most irrigation is automated nowadays. Automation is more likely to be excessive than insufficient. Desiccation, wilting and other symptoms of insufficiency of irrigation are obvious. Symptoms of saturation may not become obvious until too late for remediation.
Old fashioned irrigation systems were quite thorough, and technically sustainable. They broadcast generous volumes of water over any vegetation that required it. Their systems were too simple to need much adjustment. Their metallic composition was very resilient. That is why so many old systems were in service for so long. Some continue to function.
However, such old fashioned irrigation systems were not perfect. Their consumption was not as sustainable as their plumbing. They wasted water on vegetation that needed less, and pavement. Some of the broadcast water evaporated before reaching any vegetation. Without automation, old irrigation systems operated when convenient for their operators.
Modern irrigation systems are typically more efficient. Automation allows them to operate prior to sunrise to limit evaporation. Most modern systems apply water directly to the soil. This leaves no irrigation water to evaporate from foliar or other surfaces. Also, it prevents evaporation from airborne broadcast irrigation water. Evaporation innately wastes water.
Of course, modern irrigation systems are no more perfect than old systems. Groundcover and lawns still rely on broadcast irrigation. Such systems still waste water on pavement. Automation can actually waste water if not adjusted manually for rain and other weather. Only the most modern automation adapts to weather. No system responds to vegetation.
Consequently, irrigation can become either deficient or excessive as vegetation matures. Many native species need regular irrigation only as they disperse roots after installation. They are likely to rot with the same irrigation as they mature. Many tropical species need more water as they grow. Some vegetation, as it grows, can obstruct broadcast irrigation.
The complexity of modern irrigation systems complicates their maintenance. Automation is merely one component of the infrastructure. Emitters of drip irrigation sometimes need relocation or replacement. They are sometimes difficult to find below healthy vegetation. Because components are plastic, they are not as durable as old fashioned components.
Remember when the Brady Bunch went to the Grand Canyon? Mrs. Brady read aloud from a brochure about how the Grand Canyon was formed by erosion of the Colorado River. Peter then commented, “Wow! No wonder you tell us not to leave the water running.” Too much watering in the garden certainly will not cause a canyon to form, but can cause all sorts of other big problems.
Roots rot if the the soil is constantly too wet. If the soil stays saturated, roots suffocate from the lack of aeration. Trees that survive saturation of deeper soil strata will disperse their roots shallowly near the less saturated surface, and will consequently be unstable. Besides, excessive watering is wasteful.
There are too many variables, such as exposure, drainage, humidity and temperature, to prescribe irrigation schedules that work for every site. Just remember that most plants like the soil to drain enough for the surface of the soil to at least look somewhat dry before getting watered again. Moss on the surface is an indication that things are too wet. Plants that like more water, like azaleas, rhododendrons, fuchsias, ferns and impatiens, do not mind if the soil stays somewhat damp, but only if the soil is porous and drains enough to also be aerated.
The most drought tolerant plants, which are generally also the most sensitive to excessive irrigation, ironically like to be watered somewhat regularly for the first few months after getting planted. This is because they are so reliant on well dispersed root systems. They need less, if any, watering once their roots get dispersed.
Watering should be done in the morning so that plants can soak in the water during the day, and the area can dry somewhat before the following evening. It is also better to water less frequently and a bit more generously than to water too frequently. This allows time for drainage and promotes deeper rooting. Fungal organisms associated with rot and foliar diseases proliferate overnight if the ground is damp at the surface and the air is humid.
Except for the few plants that like humidity, and those that need to be rinsed of aphid and honeydew, there is no need to wast water on foliage where it is simply lost to evaporation. Water should be applied to the soil where it is needed.
More than a week ago, many of us were astonished to witness countless drops of water miraculously falling out of the sky! What could this be? Where did this water come from? It is actually not such a mystery. These unfamiliar falling drops of water are merely a type of weather known as “rain”. “Rain” is actually nothing new, and happens every winter. Typically, there should have been an abundance of “rain” by this late in winter.
The problem with “rain” is that it is wet. Whatever it encounters also becomes wet, and often messy. Wet dirt becomes mud. Wet roads are hazardous to traffic. It is uncomfortable to go outside to do any gardening when everything is wet and muddy.
However, “rain” is very important to everyone’s survival. It is what moves water from the oceans back onto land, so that it can be collected and used for the many things that water is needed for. “Rain” also brings needed water to gardens, landscapes, and even the forests outside of urban areas. In one way or another, every living thing needs “rain”.
But wait! There’s more! “Rain” so efficiently waters gardens and landscapes that no other watering is needed! Most watering systems should therefore be turned off as long as there is enough “rain” to keep everything wet. Even when the “rain” stops, cooler temperatures and higher humidity keep things from drying as efficiently as they would during warm summer weather. Consequently, most watering systems can remain off until after winter, when the “rain” stops until next winter, and the weather gets warmer.
Actually, the only plants that may want water are those that are sheltered from the “rain”, and perhaps a few large potted evergreen plants that continue to lose enough moisture by evaporation from their foliage to get a bit dry between periods of “rain”. Even these sheltered and potted evergreen plants use less moisture this time of year because they are less active, and evaporation from their foliage is limited by the weather.
Remember; for plenty of moisture that is one hundred percent natural and absolutely free, try “RAIN”!
Tony Tomeo 