Gardening Tip: Naturalizing with Sunflowers and Other Native Wildflowers

Native plants in the Sunflower family naturalize well in gardens.

Many plants in the Sunflower family bloom in summer or fall.  They bring welcome color to the garden and provide food for pollinators and seed-eating birds.  Another nice feature: many of them are easy to grow from seed.  That makes them perfect plants for naturalizing.

The term naturalizing refers to using flowering plants in a way that mimics Mother Nature.  People often speak of ‘naturalizing bulbs’.  But plants that produce viable seeds can also be used to naturalize.  The trick is to spread the seed about the garden in a way that looks natural.  And the best way to do that is to observe how plants group themselves in nature.

In the wild, Sunflowers often cluster in areas with optimal growing conditions.

In the Western U.S., plants in the Sunflower family (Asteraceae) are easy to observe in nature.  In a natural setting, plants often occur in clusters spread across the landscape.  There are often areas between these clusters: places where conditions are poorly suited for the establishment of plants by seeds or runners (rhizomes).

Native Lupines and Phlox form a lovely natural pattern.

The establishment pattern can also indicate wind patterns, since many small seeds are distributed by wind.  This is true of seeds specially adapted to wind distribution (those with feathery ‘parachutes’), as well as seeds that are simply blown along the ground.  And several species of plant are often interspersed, forming interesting patterns (above).

When naturalizing native flowering plants in the garden, you can’t go wrong by following the patterns of nature.  This can be achieved in at least three ways: 1) by letting plants re-seed themselves; 2) by harvesting annual plants (or portions of perennials) and laying them in a desired setting; 3) by collecting seeds and planting them in natural-looking clusters.

When native plants self-seed, the seedlings often cluster near the parent plant.

Letting plants re-seed themselves

This is the easiest method of all.  It also produces a natural-appearing distribution of plants, since the same forces that distribute seeds in the wild are at work in the garden (above).  Self-reseeding works for both annuals and perennials – even plants grown in containers and set out in the garden to re-seed.  The disadvantage of this method is that the process requires time.  To establish plants in several areas of the garden more quickly, you’ll need to give Mother Nature a helping hand.

We call this the 'lazy naturalizer' method. It is a good method
 for naturalizing some plants.

Re-seeding using whole (or portions) of plants

We call this the lazy naturalizer method.  It works for annuals, perennials that need to be culled, or perennials that you cut back after seed is ripe. This method does a good job of producing natural looking plant clusters, in desired areas of the garden.  And it’s often the easiest way to deal with tiny seeds.

Simply wait until seeds are ripe on the plants (pods open, seeds are dry, or birds are starting to eat them).  Harvest entire plants (or cuttings with seed pods/heads) and simply place them on bare ground in the desired spot. The dying plants will look a little untidy during fall (above).  But they provide a protective mulch over winter and will often break down by the following spring. They also protect seeds from seed-scavenging birds (somewhat).

You can stomp on the dried plants - or cut them up into smaller pieces to make them less conspicuous - for fall and winter. In spring, new seedlings will emerge, protected by the natural mulch.  There may be too many seedlings.  You can thin them (or, if you are lazy, just let nature take its course).

Seeds are best dried and stored in paper bags in a cool, dry place.

Collecting and spreading seed

You can also collect the seed and store it until it’s time to plant (more on that next month).  Let seeds dry on the plants.  Harvest the dry seeds and store in paper bags (or glass jars) in a cool, dry place until planting. If seeds grow in papery pods or in a typical sunflower ‘head’, you can harvest entire pods/heads, place them in a paper bag in a cool, dry place (above) and let them fully dry. Seeds can then be more easily separated  and stored.

When planting, remember the lessons of nature. Plant clusters of seeds across the landscape to give a natural appearance. Intersperse seeds of different species to add interest and look more authentic.   And be sure to plant seeds on bare ground or in areas with only a thin inorganic (gravel) mulch.

Success!! A new plant from seed.

We hope you’re inspired to try these suggestions for naturalizing plants by seed. These methods work well for any plants that produce plenty of viable seeds (note: some cultivars to not).  The sunflowers come to mind: sunflowers, goldenrods, cone flowers, asters, rabbit bushes, etc. all naturalize easily.  But wild tobaccos, milkweeds, valerians, four-o’clocks, ranunculus, buckwheats, campanulas and many native grasses, bulbs and wildflowers also naturalize well.

_____________________________________________

 

We welcome your comments (below).  You can also send your questions to: monaturesmontrosegarden@gmail.com

 

Gardening Tip: September is Planting Month

Fall is a great time for planting native plants

For many Four Corners gardeners, the question of when to plant trees, shrubs and perennials is an important one.  Some advocate planting in spring, when the ground is damp and before temperatures become too hot. But there are also good reasons for planting in the fall, particularly when establishing native plants.  Here at Mother Nature’s Montrose Garden we’ve tried both planting seasons with good success.  But our major planting has always been in the fall.  Here’s why.

First, the late summer/early fall monsoonal rains often soak the ground, making planting and establishment easy.  Fall rains also give the plants a good start; there’s nothing like a good rain to perk up newly planted specimen.

Another advantage is the fall temperatures.  In general, temperatures are moderately warm and the days are still fairly long. Moderate temperatures are optimal for many of our native plants.  In fact, many native perennials have a second growth spurt in the fall. Air and soil temperatures that are neither too hot nor too cold are just right.  And in many areas, the cold weather is still a month or six weeks away, in mid to late October.  That’s often plenty of time for a new plant to prepare for winter.

There’s a third good reason for planting in fall: local native plants are programmed to grow – and particularly to establish their roots – in the fall.  Once again, the plants are adapted to our rhythms of temperature, soil moisture and humidity.  The optimal fall conditions promote growth in general.  As an added bonus, many plants can actually sense the shorter days and cooler night temperatures. This provides added stimulus to put down a good root system. 

 

Place your plants out to be sure you like the location.

In summary, planting native trees, shrubs and perennials in September works with the patterns of nature to give new plants a good start.  The trick is to plant as early in September as possible – but not when the weather is hot, dry and windy.  That’s why many Four Corners gardeners’ plant in the second or third week of September.

On the topic of planting, here are a few additional tips to increase your success with fall planting of Western native plants:

• Be sure the ground is moist.  If rains have not moistened the ground, give the whole area a good soaking the day before planting.  

Hole size: slightly bigger than pot size

·         Dig a planting hole that is just a little bit wider and deeper than the pot in which the plant is growing (above). The old ‘wisdom’ of digging a big hole doesn’t work as well for native plants.  The sooner a native plant’s roots can grow into the garden soil the better; a smaller hole accomplishes that.

·         Don’t amend the soil in the planting hole. Amendments are not needed, and may actually discourage good root growth.  Just backfill the bottom of the hole with a little loose soil; that’s all you need to do.

·         If the soil surrounding the hole is dry, fill the hole with water and let it drain before planting.  Once again, this will encourage roots to grow out into the surrounding soil.

Hit sides of pot to loosen plant.

Gently remove plant

·         Remove the plant from the pot gently. Hit the sides and bottom of the pot firmly with your hand to dislodge the plant.  Then turn the pot upside down, and let the plant drop into your hand (above)

Loosen roots with your palm or fingers

·         Loosen the roots by rubbing the root ball with the palm of your hand (above).  Just a gentle rub, all over, to loosen pot-bound roots and stimulate them to grow.

·         Check the depth of the hole. The potting soil surrounding the plant should be level with the ground.  Add or remove soil as needed (below) before placing the plant in the hole.

Pot soil should be level with garden soil.

·         Fill in the planting hole with garden soil.  You’ll have plenty left from digging the hole.  Be sure to fill in the holes all around the plant.

·         Press down soil firmly around the plant.  We often also gently step on the soil to be sure that plant roots are in good contact with the soil.  This step is critical for getting roots to grow into the soil and establish a good root system quickly.

·         If no rain is predicted, water in the plant with a good sprinkling with a hose or watering can.

·         Mark the new plant with a colored flag. You may also want to identify the plant with a permanent marker.  For more see: https://mothernaturesmontrosegarden.blogspot.com/2019/10/gardening-tip-mark-your-perennials.html

·         Take a picture of the new plant for your records.

·         Reward yourself with your favorite beverage!

 

For a copy you can print see: https://www.slideshare.net/cvadheim/garden-tips-planting-native-plants

 ________________________________

 

We welcome your comments (below).  You can also send your questions to: monaturesmontrosegarden@gmail.com

  

Plant of the Month (September) : Hummingbird Trumpet/ California Fuschia – Epilobium canum

 

Hummingbirds are the jewels of Western gardens.  With their brilliant colors and fascinating behavior, they bring hours of enjoyment.  That’s why many of us include ‘hummingbird plants’ in our garden palette. One such plant, which graces fall gardens with its orange flowers, is the Hummingbird trumpet, Epilobium canum.  The scientific name is pronounced epi-LOBE-ee-um  CAN-um.

Epilobium canum is a member of the Onagraceae (Willow-herb) family that includes such garden favorites as the common garden fuschia, evening primroses, Clarkias, Gauras and native Camassonia species.  The genus Epilobium includes the lovely native Fireweeds as well as California Fuschia.   The taxonomy (classification) of the Willow-herb family is still being sorted out – so we may need to update this post in the future.  Long-time native plant enthusiasts still sometimes call Epilobium canum by its older – but more interesting – name: Zauschneria californica.    The name Zauschneria honored the 18th century German botanist Johann Baptista Josef Zauschner.    The name Epilobium refers to the fact that flower and seedpod occur together and the species name canum refers to the ‘hairy’ aspect of this species.

Epilobium canum is a plant of the North American West, growing from Oregon and Wyoming to Baja California and Northern Mexico.   There are currently four recognized sub-species (note: some taxonomists group ssp. garrettii and latifolium together): Epilobium canum ssp. canum (California Fuschia); E. canum ssp. garrettii (Garrett’s Hummingbird Trumpet); E. canum ssp. latifolium (Mountain Hummmingbird Trumpet); E. canum ssp. angustifolium (Narrowleaf Hummingbird Trumpet).

Sub-species canum and angustifolium are endemic to California. Sub-species garrettii grows on dry rocky slopes and chaparral, up to 5500 ft. elevation, in CA, WY, ID, UT and AZ. Sub-species latifolium, including the formerly known Epilobium/ Zauchneria arizonica, is found on rocky slopes and canyons, primarily at the highest elevations, 7000-10000 ft., but sometimes as low as 3500 ft. in CA, AZ, s.w. NM & adjacent Mexico. [1]   

As you might expect, sub-species and cultivars vary in their hardiness, as well as their heat and drought tolerance.  If you live where winter temperatures dip to zero degrees F. (or below), sub-species garrettii (USDA Zones 3–10) and latifolium (Zones 5-9) and some of their cultivars offer your best choices.  As always, be sure to check the USDA Zone for a plant before you purchase.  If you live in a warm-winter area, you can grow most of the sub-species and cultivars, but some may require more water.

In the garden, Hummingbird trumpet adds a spot of bright color at a time when the many summer-blooming species are past their prime.   This species really begins growing in earnest in late spring/summer.  In colder climates, the plant dies back significantly – and is also eaten by hungry critters - in winter.  In mild winter areas, gardeners cut the stems back after blooming to achieve the same ends.    The plants start sending up new stems in spring – and really achieve their full growth in summer. 

Hummingbird trumpet is a spreader, so don’t be surprised if a clump of Epilobium increases in size over the years.  The stems of Epilobium canum are slender, part-woody and wand-like to almost vine-like.  They usually form a mounded clump, but it may fill in around other plants.  The leaves are long and narrow or lance-shaped.  The foliage color varies from a medium green, through pale blue-green to silvery.  In fact, the natural variation in foliage color is the source of several common horticultural cultivars.

Hummingbird trumpet’s flowers are spectacular.  They are 1-2 inches long and up to an inch wide.  They range in color from orange to almost scarlet red and are tubular or funnel-shaped. Some cultivars are even a pale orange! The anthers (male flower parts that produce the pollen) as well as the female parts extend well beyond the fused petals.   When a hummingbird reaches into the flower tube to sip nectar, pollen sticks to its head. The pollen is then deposited on the stigma of subsequent flowers.

The flower color, shape and location of the sexual organs are all good clues that Hummingbird trumpet is pollinated by hummingbirds.   Hummingbirds are attracted like a magnet to these glorious flowers.   Locate Epilobium near a seating area and you can observe hummingbirds from a distance of only a few feet!   It’s fun to watch hummingbirds chase others from ‘their’ flowers!

Epilobium canum is easy to grow in western gardens.  It can take just about any local soil – even those with pH around 8.0.   Depending on the sub-species/cultivar it does well in full sun or part-shade.  In full sun the form of the straight species will often be a 2-3 ft. mound; in part-shade the stems create a low ground-cover (see below).   As with common garden fuschias, you can pinch the tips of growing stems to form a fuller plant.

Epilobium canum adapts well to garden conditions.  Species from lower elevations are quite drought tolerant, but look better with infrequent summer water (Water Zone 2; see https://mothernaturesmontrosegarden.blogspot.com/2020/07/creating-your-colorado-friendly-garden.html). Sub-species from higher elevations do best with occasional summer water (Water Zone 3).    Plants can take winter flooding, which is useful for those of us who garden in clay soils.   And in our experience, Epilobium is quite disease- and pest-free.

Yearly maintenance is minimal.  In warm winter areas, cut the branches back to 1-2 inches after flowering to keep the plant looking tidy and healthy. In colder areas, leave the branches on over winter, then cut back in spring.  You can use your cuttings to produce new plants if desired.   You can also let the plants naturalize by seed.  The seeds have fluffy wings (see above) that float on the wind and re-seed throughout the garden.   The natural look is lovely – but the choice is yours.

Epilobium canum can be used in many ways in the garden. It makes a nice fall accent plant in mixed water-wise beds.   We like it mixed with other native shrubs, where it fills in the bare spaces over time.   Hummingbird trumpet can be used as a groundcover – alone or with other native groundcover plants. It will even do spectacularly in a large container.  It’s a perfect accent along walkways or bordering a seating area.  It naturalizes in favorable spots throughout the garden if you let it go to seed.

There are several horticultural cultivars (types selected for garden use) that are readily available at native plant nurseries and sales. In cold-winter areas, try cultivars of subspecies latifolium and garrettii.

Epilobium canum ssp. latifolium   

‘Northfork Coral’ – USDA Zones 5-10, with coral colored flowers. 1-2 ft tall, 2-3 ft wide.

‘Woody's Peach Surprise’ – USDA Zones 5-9. Low-growing form: 6-8” tall by 18” wide. Has unique, pale peach flowers.

Epilobium (Zauchneria) canum [var. arizonica] 'Sky Island Orange' – USDA Zones 5-8. Grows 2-3 ft tall & wide. Flowers red-orange. Wide drought tolerance (10-30” water per year).

Epilobium canum ssp. garrettii

'Orange Carpet' – Hardy (from Idaho; USDA Zones 5-9). Lower-growing  4 to 12 inches high, 2-4 feet wide. Does best with afternoon shade in hot gardens

Another choice for hot summers is Epilobium ‘Everett’s Choice’, from the California Bay Area, which can take the heat. One of the lowest growing of the Epilobiums (3 to 6 inches high, 3 foot spread or more). It’s very drought and deer resistant, and more cold resistant than most California forms (hardy to -10°F).

Because Hummingbird trumpet is a popular garden plant, new cultivars are being introduced all the time.  We suggest that you purchase cultivars in the fall, when you can observe the flowers and foliage colors at their best.

We hope you’ve been inspired by this lovely Western native plant. Most gardens have a spot for one or more of these charming plants.  You’ll love the bright accent in your late summer/fall garden.  It’s a real treasure - unless you detest the color orange!

For a gardening information sheet see: https://www.slideshare.net/cvadheim/gardening-sheet-epilobium-canum-238401468

For more pictures of this plant see: https://www.slideshare.net/cvadheim/epilobium-canum-garden-photos

For plant information sheets on other native plants see:

 

________

1.       https://plants.usda.gov/plantguide/pdf/pg_epca3.pdf

 

_________________________________

 

We welcome your comments (below).  You can also send your questions to: monaturesmontrosegarden@gmail.com

Garden Pollinators: Syrphid flies (Hoverflies; Flower Flies)

 

The word ‘pollinator’ conjures up images of Honey Bees for many.  But the world of pollinators is far more complex.  Our Garden Pollinators series features some of the many interesting pollinators seen in Western Colorado gardens.  For more on pollinators in general – and tips for attracting pollinators to your garden – see: https://mothernaturesmontrosegarden.blogspot.com/2020/06/life-friendly-gardening-planning-for.html

Today we’d like to focus on an important group of pollinators, the Syrphid flies. Syrphid flies, commonly known as Hover flies and Flower flies, are frequent visitors to Western gardens. They are most often seen hovering near flowers.  But many gardeners don’t appreciate their significant role, not only as pollinators but also as beneficial predators of well-known garden pests.

The Hoverflies belong to a large family of true flies – the Family Syrphideae. This family contains nearly 6000 species and 200 genera; there are around 900 species in North America alone [1, 2].   Syrphid flies inhabit much of the planet, the one exception being the continent of Antarctica. Few species also live in the very driest deserts. Syrphids are an old group of insects. Fossil species date back to the Eocene epoch (about 56 to 33.9 million years ago).

Like the native bees, Western U.S. Syrphid Flies range in size from small (less than ¼ inch) to about the size of a Bumble bee (nearly 1 inch). For examples of some common species see: https://en.wikipedia.org/wiki/Hoverfly#/media/File:Syrphidae_poster.jpg 

Many species superficially resemble either bees or wasps (protective mimicry, also known as ‘Batesian mimicry’).   Some have bodies that are compact and dense (like a bee) with a rounded head; others have slender bodies more like wasps. Their coloration may also mimic that of bees and wasps, often yellow with dark stripes.   However, Hover Flies differ from bees and wasps in several important ways: 1) a single pair of wings (bees have two pairs) held in a characteristic, swept back (‘bomber’) position when perched (see above) ; 2) no stinger; 3) very large, compound eyes (compare above); 4) short, segmented antennae (see above); 5) mouths with relatively short, non-specialized mouth parts

Adult Flower flies are attracted to flowers as a source of food.  They need both nectar (for energy) and pollen (for reproduction).  They are superb fliers, with the ability to hover and fly backwards, a rarity among insects.  All of this requires lots of energy (nectar).  Some Flower flies specialize in a limited range of flower species.  Many, however, are generalists, visiting many types of flowers and spreading pollen (pollinating) as they go.  Pollinator studies in Colorado’s prairie found that ‘44% of flowering plants species investigated were pollinated by 16 hoverfly species.’ [3]  They are likely also important pollinators in Western gardens.

In general, Flower flies are attracted to plants with many small, open flowers, often those growing in dense clusters.  The yellow and white flowers of plants in the Sunflower (Asteraceae), Carrot (Apiaceae or Umbelliferae) and Buckthorn (Rhamnaceae) families, as well as those of the Borage (Boraginaceae) and Rose (Rosaceae) families provide both nectar and pollen.[4] As plants from these families are often planted in gardens, it’s not surprising that Flower flies are common garden visitors.

Wind pollinated species, such as grasses, sedges, pines, willows, cottonwoods, aspen and alders can be important sources of pollen, particularly for forest-dwelling species.  Pollen provides the protein needed for egg production. So female Syrphid flies can be seen collecting and eating pollen, in addition to sipping nectar.

The life cycle of Syrphid flies contains several stages, starting with the egg and ending with the adult. Syrphids undergo a complete metamorphosis from egg to larva, pupa, and adult (see below).

The larval stages look very different from the adult. Larvae are legless and blind, emerging from white-gray eggs onto the plants on which the eggs were laid. They can be distinguished from caterpillar larvae by their tapered head, lack of legs and opaque skin (can see internal organs).  The larvae grow quickly, through several stages (instars). All this growth requires food, and this is where many Syrphid species are invaluable as beneficial insects.

Larvae of many species eat aphids, thrips and other soft-bodied insects, the banes of many farmers and home gardeners. And they eat a lot; it’s estimated that a single larva consumes approximately 1200 aphids in its life. No wonder some farmers now plant flowers specifically to attract Syrphids to their vegetable crops.  Larvae are even raised and released in greenhouses to pollinate crops and control such pests!

We hope you’re now convinced that Flower flies can play an important role in garden ecosystems, providing both pollinator and insect control services. In fact, you may want to attract more Syrphids to your home garden.  The trick is to plant the plants they favor, being sure that some are blooming from spring to fall. 

Since Syrphids (and other beneficial insects) are killed by insecticides, you’ll want to use these chemicals only when absolutely necessary. Beneficial insects are particularly susceptible to insecticides that contain neonicotinoids and synthetic pyrethroids.[6] A garden with many beneficial insects and birds may require little or no use of such chemicals.

We hope you’ve enjoyed learning about the Hover flies.  Go out in your garden and look for them.  They are fascinating and welcome creatures!

 ______________

1.       https://en.wikipedia.org/wiki/Hoverfly

2.       https://bugguide.net/node/view/196

3.       https://beyondpesticides.org/dailynewsblog/2017/07/polli-nation-pollinator-month-hoverfly/

4.       https://www.pacifichorticulture.org/articles/hover-flies/

5.       http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artmay07/cd-hoverflies.html

6.       https://beyondpesticides.org/dailynewsblog/2017/07/polli-nation-pollinator-month-hoverfly/

____________________________________________

 

We welcome your comments (below).  You can also send your questions to: monaturesmontrosegarden@gmail.com

 

Creating Your Colorado-friendly Garden: 7.b – Designing an Irrigation Plan

 

Last month we discussed several topics related to developing a water management plan: determining your water goals, creating a Water Zone plan and managing/harvesting precipitation water.    If you’re just joining the ‘Designing Your Colorado-friendly Garden’ series, we suggest starting at the beginning (https://mothernaturesmontrosegarden.blogspot.com/p/creating-your-colorado-friendly-garden.html) and working forward.  The monthly activities will help you design an attractive, functional, sustainable garden you’ll enjoy for years to come.

Introduction and Background

By this point you’ve probably guessed that the ‘irrigation system’ in a Colorado-friendly Garden is not likely to be a conventional, one size fits all ‘sprinkler system’.  Instead it will be tailored to the Water Zone Plan, site characteristics and the needs of the gardeners themselves.  Part of the trick to designing a functional and enjoyable garden is to look honestly at your own needs and constraints.

Proper watering of native (and other) plants is at least as important as selecting the right plant for a given water zone.   More native plants die in home gardens due to improper watering than almost any other cause.  An irrigation system that allows you to water plants easily and properly is key to a successful garden.  And because your garden will mature – and climate will change – your irrigation system must also be flexible.  

Your ‘irrigation system’ can be anything from a simple spigot and hose to a complex automated irrigation system (or some combination of both).    There’s no one system that’s right for all gardens.  If your landscape plan includes more than one Water Zone – or if your site is anything other than a small flat piece of ground – you may need to use several types of irrigation methods to water everything properly.   Fortunately, you have several options to choose from – and plenty of resources to turn to for advice.

We summarize the benefits, limitations and best uses for the most common types of irrigation methods used in Western gardens at: http://www.slideshare.net/cvadheim/irrigation-methods-for-southern-california-gardens   This table reflects our experience with watering native plants in Southern California as well as Western Colorado; other experts may present other points of view.  Realize that the relative advantages and disadvantages vary with climate, soil and other factors.  Much of the readily available information on watering Colorado native plants – both on-line and in books - is directed to gardeners on the Front Range, the eastern plains or in desert areas.  While generally useful, remember that such information is not specific to our unique climate(s) in western Colorado. 

Planning an Irrigation System: Example from 112 Willow St.

It’s easier to plan your own irrigation system once you’ve seen a worked example.  So, let’s design a new irrigation system for 112 Willow Street, an example of a small Western suburban garden.   We will present an example of a larger garden, Mother Nature’s Montrose Garden, next month.

The current irrigation system for 112 Willow Street is shown on the site map (above). The ‘system’ may be similar to your own.  It consists of two separate water lines: one line that supplies conventional sprinklers (front and back) and a second supplying 4 hose bibs (spigots).   The sprinklers are controlled by two timers: one for the front yard and one for the back.  The backyard timer has two stations: the northern part of the backyard (nearest the house; station 1) and the rest (station 2). 

As discussed before (July, 2020), the front yard will be left as is for now; the automated sprinkler system will continue to water this area every 10 days for the near future.  However, in considering the irrigation needs of the entire yard, we realize that an additional spigot at the east side of the front yard would greatly facilitate watering the ‘meditation garden’.  We add this to the Irrigation System Map, even though the installation may take place several years in the future.

The backyard sprinkler system won’t need a lot of modification to make it suitable for irrigating the new lawn (see above).  One sprinkler head is superfluous and another would be better if moved slightly.  That and some new, water efficient sprinkler heads with the correct spray radius (8-10 ft) and we’re in business.    The sprinkler system will likely provide all the water needed for the ‘shady seating’ area as well.  If not, we can supplement occasionally with a hose and sprinkler.  If you need more information on irrigation systems and their design we highly recommend the following tutorials: http://www.irrigationtutorials.com/ .

Planning an irrigation system for the vegetable garden requires deciding how the space will actually be used.  The gardeners like raised beds, and there’s room for at least two different configurations, each providing 120-130 square feet of growing space (see below).  The gardeners will consider how to arrange the raised beds and will design them in October (2020).  Whatever the configuration, they’ll want an irrigation system that’s flexible and as water-wise as possible. 

The gardeners decide to use inexpensive ooze-type soaker hoses, covered with mulch, to water the raised vegetable beds.  This will allow them to water only the planted areas, leaving the pathways dry.  Installing a hose bib for each bed will give the most flexibility. The soaker hoses can be attached directly to the hose bib in each bed. And each bed can be controlled separately, providing the right amount of water for each crop through the growing season.  

During most of the year, the gardeners will control the water manually, as needed. This is, in fact, the most water-efficient method of irrigation.   But what about during the three week summer vacation when the gardeners are routinely away?

Depending on how we design the irrigation system, we can have all the beds on a single, multi-station timer or use individual, battery operated timers for each bed.  In our experience, many smaller yards, particularly if landscaped with water-wise plants, don’t require sophisticated (and costly) irrigation systems with sensors.   Inexpensive hose timers are readily available, easy to use and work well in many situations.  You can even store them away when they aren’t needed to extend their life.   For more advice on timers and sensors see:

• http://www.sandiego.gov/water/pdf/waterwisegardening.pdf
• http://www.irrigationtutorials.com/#sprinkler
• http://www.water.ca.gov/wateruseefficiency/docs/irrigation_controllers_0903.pdf

 

The ‘butterfly garden’ area, which is on a 6-9% slope, has presented an irrigation challenge in the past.   The gardeners plan to install primarily water-wise plants – and place the most drought-tolerant of these on the drier top of the slope.  This will go a long way towards making the area less problematic.   But even though the plants will be Water Zone 2 at maturity, the ‘butterfly garden’ will require summer water during the establishment phase (likely the first year or two after planting) and occasionally thereafter. The gardeners will need an irrigation method that is flexible; and once again, they have several options.

One possibility is to use drip irrigation for the first few years.  While some native plant nurseries recommend against drip irrigation, in fact this method can be useful in some circumstances in our part of Colorado.   Drip irrigation has come a long way in the past decade. For a good, thorough tutorial on drip irrigation see  http://www.dripirrigation.com/drip_tutorial.php .  There are many more choices of emitters including micro-sprinklers and soaker-emitters.  These can be used successfully with Colorado native plants under certain conditions.  In our experience, drip irrigation is best used to get plants started or for container plants.   

There are several downsides to drip irrigation.  Drip systems can be costly, particularly if you pay to have them installed. The emitters can plug – or even pop off – during irrigation, so gardeners should inspect their emitters regularly for proper functioning.  Don’t assume your plants are being watered adequately unless you check your drip system routinely!!  

As the root systems grow, the emitters need to be relocated to provide optimal water to the plants. Remember that the root systems of many native plants expand quickly; failure to move emitters around growing plants is another common mistake made by home gardeners.

In our experience, simple soaker hoses can also be used on small garden slopes, provided that drainage is adequate and watering is done over several days.  The secret is to water the area, using a slow seep rate, until runoff starts.  After a few times you’ll know just how long this takes.  Then water again in the next day or two.  This will provide a good soaking, and can be repeated every other week, or as needed, during the first summer.  The advantages of soaker hoses over drip are several: 1) lower cost; 2) lower maintenance requirements; 3) more even water coverage (good as plant roots grow out); 4) if covered with mulch they last for years, providing for supplemental water when needed. 

Because the top of the slope dries out before the bottom, the gardeners will use several soaker hoses to give them maximal flexibility.  The soaker hoses will be installed once the ‘butterfly garden’ is planted to insure good coverage.  After securing the hoses with landscaping staples (also called ‘landscape fabric pins’ or ‘sod staples’), they will be covered with mulch.  They will be connected to the nearby hose bib (spigot) with a hose when in use.   When not in use they will be completely invisible.

The gardeners could also choose to water the ‘butterfly garden’ with a sprinkler that attaches to a hose.  There are many options available – including ones that are quite attractive.  This option has the advantage of being very flexible; you can just water the dry areas and not worry about areas that don’t need water.   It also provides a good approximation of rain if you need to water during winter/spring dry spells.

But any type of overhead watering, whether with conventional sprinklers or those attached to a hose, has several disadvantages.  First, overhead irrigation is less water efficient: in dry climates like ours, some water will evaporate before reaching the ground and more will evaporate from the mulch without reaching the ground beneath.   The other disadvantage, particularly for summer watering, is that overhead watering increases the chance of fungal diseases.  Wet leaves and warm conditions favor the growth of fungi; and leaf splash can spread fungal spores from one plant to the next.

As currently envisioned, the ‘meditation area’ will not need much irrigation once established and the gardeners plan to use stored rainwater to supply some of the water in the future.   The irrigation system for this area will depend on the landscape design for this area.   The back of the neighbor’s garage abuts this area – an ‘ugly view’.   The arrangement of the seating – and choice of plants – will dictate the irrigation needs for this area.  If the homeowners choose a trellis and vine to mask the ‘ugly view’ they will need to supply irrigation to the vines.  Native honeysuckle vines would do well and require only occasional water once established.  We’ll have to wait to finish the irrigation system for the ‘meditation area’.

On further review of the ‘near final’ irrigation plan for 112 Willow, the gardeners decide that having a spigot to water the meditation garden will be a necessity as soon as that area is installed.  The idea of watering the area from a backyard spigot doesn’t seem workable.

 

Designing Your Irrigation Plan

We suggest the following steps in designing your irrigation system:

1. Using a copy of Site Map 2, map your existing irrigation system
2. Compare your current system with your Water Zone map.
3. Decide what parts of your current irrigation system are compatible with the Water Zones in your new garden.   You may be surprised; conventional sprinkler systems can sometimes be modified to work.  If parts of the system are no longer needed, they can be capped off. And new sprinkler heads can decrease water loss to evaporation.

 

4. Consider how you’ll supply water to Water Zones 1 and 2.  Remember that new plants will need to be watered for at least one or two summers until they are established – and Zone 2 and 3 plants will need occasional summer water thereafter.   

 

Once you’ve decided on possible irrigation choices, we suggest that you step back and evaluate.  In fact, you may want to put your plans aside for a day or two.  Then ask yourself the following questions:

·         Are these choices consistent with the amount of time/effort you want to spend watering the landscape?

·         Are they feasible in terms of cost, skills needed to construct, maintenance requirements?

·         Look at your Base Map 2; are you sure you haven’t located irrigation lines where they will interfere with anything critical (like gas & electric lines).   

·         Is the ‘system’ flexible (for example, can you change if the initial method doesn’t work well; can you use overlapping systems if you need to water one part of a Zone a bit more)?

·         Have you planned enough: spigots?  Sprinkler heads?  controllers?   Are these in convenient locations?   If not, now is the time to do something about it.

 

Once you’re happy with your plan then construct a final Irrigation Plan map.   Be sure to note location of spigots, location of irrigation pipes, sprinkler risers (if any), pop-up irrigation heads (and the types of heads), and location of drip irrigation lines and soaker hoses (if any).  

 

Additional Internet Resources

https://cmg.extension.colostate.edu/gardening-resources/online-garden-publications/water-wise-landscaping-xeriscaping/

https://coloradowaterwise.org/Resources-and-References

Xeriscape Colorado: The Complete Guide. CL Ellefson and D Winger. 2004, Westcliffe Publishers, Englewood CO.

_______________________________________________

We welcome your comments (below).  You can also send your questions to: monaturesmontrosegarden@gmail.com