Tag Archives: drought tolerant

Roses in the Low-Water Garden

Roses are old-fashioned favorites that often remind gardeners of their mothers or grandmothers or of lush gardens in the South, where both water and sun were readily available from nature. But I see fewer roses in gardens now, partly because they’re associated with lots of patience and care, and partly because some of the hybrid roses need more water than a low-water garden can – and should – provide. It’s also strange to picture a tall, hybrid tea rose in the middle of a xeric landscape, although a good landscape designer can always work a small rose garden into your plan if that’s what you desire.

floribunda rose in low-water garden

Friends brought us this floribunda as a housewarming gift and it fits nicely in our xeric rose garden. We watered it the first year, but only a little this spring.

Many shrub-size roses fit in nicely with the look and purpose of a low-water garden. So you can have the scent and many other features of roses, as long as you’re willing to choose the right type of rose. Here are a few to consider:

Species roses. A species rose is basically a wild rose. Several species roses have grown to adapt to drought and other extreme conditions. I have several in my rose garden area, and I know one of them is a Wood’s rose (Rosa Woodsii). It can grow to at least 10 feet and has beautiful pink flowers, followed by hips all fall and winter, which the birds love. Another is a shorter, shrub-style rose that I believe is the Prairie rose (Rosa blanda), with pink flowers that fade to white in the center. The other has deep red flowers. Both have in common large, plentiful thorns and bunches of two-inch flowers in late spring.

woods rose bloom

Close-up of a Wood’s rose bloom. They’re small, but abundant on the plant’s long canes.

rosa blanda species rose

The wild Rosa blanda is only about 18 inches tall.

Native roses. In New Mexico and other Southwestern states, the Arizona Rosewood (Vauquelina californica), which resembles an evergreen oleander in its foliage and shape, or the Apache Plume (Fallugia paradoxica) both have delicate white flowers that resemble roses. The native plants have adapted to the Southwest and attract bees.

apache plume

This Apache plume (with the Wood’s rose in left background) got too dense and full. They are so easy to care for and forgiving when pruned.

Shrubs and groundcovers. Some hybrid roses have been adapted to grow as smaller shrubs and groundcovers. They’ll use less water and take up less space in the landscape. In general, they need less care than other rose types, but have long bloom periods.

Flower Carpet red

Flower Carpet Red from Tesselaar is a spreading groundcover rose that reaches no more than 32 inches high. It’s drought tolerant once established and hardy down to zone 5. Image courtesy of Tesselaar.

In fact, species, native and certain shrub or groundcover roses are all typically easier to care for and relatively disease free. Just give them mostly sun and prune according to recommendations once in early spring. You don’t have to continuously dead-head blooms, and they have adapted to lower water and the changing conditions of high deserts and mountains, so having them in your garden is more water wise. But there are a few disadvantages. The species roses are wild, which means they can sprout new canes or offshoots. The yellow one in our garden has gotten too thick and large, and will need serious pruning next spring; it’s sort of taken over the area and is shading some other plants too much.

species roses

Our rosa blanda, red species rose and taller yellow species rose to the right. It blooms earlier than the others, so we have color from early May through September.

Another disadvantage is that if you love to cut long rose stems to use the blooms in flower arrangements, you won’t enjoy these varieties as much as hybrid tea roses; their stems are typically shorter. However, if you want to walk or sit next to them in your garden and stop to smell them, or simply enjoy the beauty of the plant and blooms, you can have your roses and save water too!

Favorite Low-water Plant: Desert Zinnia

Although it’s a member of the zinnia family, the desert zinnia (Zinnia grandiflora) is remarkably different from the large annual flower we typically think of when we hear of a zinnia. Actually a member of the aster (Asteracaea) family, this tiny perennial is a delicate xeric groundcover or low shrub native to New Mexico, Arizona, Colorado, Kansas, Oklahoma and Texas.

desert zinnia flower

The desert zinnia has a big flower on needle-like leaves. I love how the flower sort of reflects the sun it loves.

Also called prairie zinnia or Rocky Mountain zinnia, the plant blooms in summer and its tiny, needle-like foliage dies back in the frost of winter, resembling dormant grass. But have no fear! The plant is there, and comes back, even spreading. I just brush up the dormant leaves as part of the spring garden clean-up, and new plants already are appearing underneath. You could also gently rake up the spent foliage in larger areas. Clearing off the old leaves exposes the new plants to more sun, which they love.

zinnia grandiflora shadow

This tiny desert zinnia is casting a morning shadow on the rock it grows from.

But although desert zinnia loves sun, it doesn’t love water. That’s right – once established, desert zinnia needs no water at all. Too much water just introduces weeds into the mix, which can be hard to pull from between the delicate foliage. If you have a period of no rain, you can give desert zinnia some water to ensure blooming. The flowers also do fine in partial shade.

desert zinnia in rocks

Desert zinnia will spread low across the ground or cascade down rocks. This weekend starts monsoon season, and I expect more blooms to appear.

Typically, the desert zinnia is about 4 inches high and spreads to nearly 15 inches wide. Each flower can reach nearly an inch in diameter, with an orange cone (Golden Eye) surrounded by three to six yellow petals. It should thrive in zones 5 through 8. It’s a great plant for erosion control and for rock gardens. I love how it cascades over and through our rock wall.

Update Your Hardiness Zone

In 2012, the U.S. Department of Agriculture (USDA) updated its cold hardiness zones. Farmers, suppliers and home gardeners use the zone designations to help standardize how well a plant can survive at average extreme minimum temperatures. In the new iteration, the USDA added two new warm zones to reflect areas in which the average low stays above 50 degrees (if only!). Of course, the zones are restricted to tropical areas of the country, such as Hawaii. Several zone boundaries also shifted to reflect warmer temperatures in several zones from the 30 years of data collection.

Maui view

If only I lived in Maui, where the zones are more like 10 to 13 and the landscape is so lush.

Read what you want from the shifts in zones, though the USDA is quick to point out that climate change trends require 50 to 100 years of data collection, and zone changes are not reliable evidence of whether there is global warming.

At any rate, if you haven’t checked your USDA zone in a few years, it’s a good idea to look again and see if it’s shifted. The USDA has given you another reason to check. The scale has fine resolution and GIS technology. This means that between your ZIP code and GIS location, you can have more accurate data to reflect the effects of, say, urban streets and buildings on your townhouse patio. It’s huge for someone like me who lives in a rural area and seldom receives accurate weather data, for instance, unless I collect it in my own back yard. The map recognized my location and pinpointed my zone accordingly as 6B.

USDA hardiness zones

Here’s a simplified image of the USDA hardiness zones. Visit the USDA site (by clicking on the image) for more detail on your zone.

Cold hardiness is not the only factor to consider, though, especially for xeriscaping. Altitude affects temperature, but also contributes to drying of plants. And wind, well, don’t get me started. I will say that wind dries a plant out and does plenty of damage to new plantings or houseplants you’re beginning to bring outdoors. You also have to consider soil and microclimates, such as those on the city balcony. On a broader scale, valley or riverbank climates differ from those of mountains or open plains.

Within your xeric garden, you can push a zone slightly by adding plenty of warmth to a plant when you place light-colored gravel under it or plant it near a south-facing wall. Or help out a plant that needs a zone cooler by putting it under the shade of a tree or on the north side of your home. Just be sure to check tags for plant hardiness zone before buying, especially from catalogs, online or in big-box stores.

potentilla and rocks

South-facing rocks keep this Ephedra in the foreground and transplanted cinquefoil (Potentilla fruitcosa) nice and warm.

Help Plants Beat the Summer Heat

It’s hot here. I thought I would never say that. And sure, it’s not as hot as Phoenix, but even mountain communities in the Southwest can warm up in summer months. When the temperatures hit the 90s, the humidity stays below 25 percent, and the winds never subside, vegetables and ornamental plants get stressed.

columbine northeastern exposure

In May, this columbine was blooming and healthy! It’s a little stressed now. Columbines grow naturally under the shade of trees, and they need deep water as temperatures rise into the 70s and higher. We mulched around the plant and put it in a northeast-facing location to help it survive summer.

Often, our first reaction is to throw more water on a plant. Sometimes, that’s what they need. Wind, sun and heat dry plants more quickly. Native xeric plants are adapted to take some of the parching sun and wind, and sometimes a gardener can overwater a plant. Here are a few tips to keep xeric plants cool, healthy and happy during the heat of summer:

  • Start with the right plant for the right spot. That means not only a native selection, but choosing sun vs. shade or the right drainage. Most xeric plants can take plenty of sun, but some need partial shade. And most don’t take kindly to wet feet, or roots that fail to dry between watering. Wet feet can happen with overwatering or if you place lavender in poorly draining soil at the bottom of a hill, or hide it under a bush that grows quickly and shades it within a year. You also can plan ahead to take advantage of shade. It’s getting too hot for my lettuce, but we’ll plant some more north of the fence holding the pole beans as soon as they get a little taller.
garden plan for shade

The sun is so bright, it’s reflecting off the spot where we hope to get some shade for lettuce and spinach. You can see the bean seedlings on the other side of the foreground fence shadow.

  • Follow the sun. When you plant in spring, the sun and shade patterns are different than they will be in mid-July and August. So keep in mind the sun’s direction and any plants or structures that might help shade a plant late in the day, when the sun’s rays are their hottest. Remember that deciduous trees might be nearly bare when you plant, but loaded by mid-June.
  • When helping a new plant get established, the typical care instructions might not apply. The plant goes into a sort of shock, much like when you recover from illness or injury. All plants need a little more water, as well as extra sun and wind protection until established. We’ve often used portable lawn chairs to provide filtered shade over new plantings in the afternoon. Old sheets or landscape fabric also work.
  • Use containers. If you have a plant that’s more susceptible to heat stress, place it in a container. You can move it around throughout the summer based on the sun’s path. Of course, if you really love the plant and have lots of time on your hands (and wheels under a larger container), you can move it around during the day, giving it morning sun and afternoon shade.

    tomato in container

    The tomato seedlings I planted in containers are doing better than many in the ground. The patio and house warmed them up during cool nights, but provide shade now on hot afternoons.

  • Water in the morning. It’s tough to find time before work, but watering early in the day loads your plant up, preparing it for the heat. And try to keep soil evenly moist. If you have a slow drip system, the irrigation can run while you get ready for work. Cover the drip hose with a nice, thick layer of mulch and the mulch will slow the water’s evaporation and help keep the ground cool. And as I’ve said before, it’s good to keep an eye on tomatoes and other vegetables and to have someone care for them if you leave town. Once the fruit sets, you can’t drown the tomato to make up for a few days of heat and underwatering. They’ll punish you.

Finally, drink some iced tea, flavored with a small bit of fresh mint. Oh, wait, that’s for me…

Start Small on Your Xeric Landscape

If you’re not an experienced gardener or feel overwhelmed by the prospect of starting a landscape from scratch or switching your entire landscape to a xeric one, why not start small?

Time, money and inexperience should not keep gardeners from enjoying a few plants in their yard. I sometimes can’t stop bemoaning the trend in believing that xeriscaping is the same as “zeroscaping.” Again, it’s not!

Even new, young gardeners and urban dwellers can enjoy a few blooms or edibles without busting their budgets, schedules or water resources. Try these tips:

  • Start with containers. If you have little space, but crave fresh herbs, enjoy a few bright blooms next to you while you savor your morning coffee outside. Or enjoy the view of hummingbirds hovering over a flower by outfitting your patio or balcony with a few brilliant containers. You could add a long, thin box with your favorite low-water kitchen herbs and a tall, round container with a salvia for color and pollinator interest. Or try a geranium, which uses a little more water, but lasts year-round in your container if you bring it indoors to a sunny location.
mint and lettuce containers

Mint in a container — where it belongs! Friends gave us these two transplants. That’s a baby mesclun lettuce mix to the right.

  • Take it one area or bed at a time. If the idea of going completely xeric in your garden is too much to handle at once, take baby steps. Convert a small area of your lawn from grass to gravel and native plants, or from high-water grass to native grass, gravel and native plantings. Or take out grass along a sidewalk or driveway and create a path with a few ornamental grasses and perennials. An easy way to conserve water is to divert rain from a downspout that pours onto, say, a driveway so that the water instead flows to a tree already in your landscape. Find plans for dry river beds with rocks to ensure the water flows to your tree.
  • Choose one or two hardy xeric perennials a year. I’m not the best person to advise patience, but if you’re short on budget and time, choose just a few hardy xeric plants to start your garden off right. The best choices depend on where you live and your USDA zone, along with the microclimate for the location you plan for the plant. Choose a perennial, a plant that will live through your winter and bloom again for at least two years. If this is an early attempt at gardening for you, go to a local nursery, where the staff can show you a few natives for your area that are hardy and easier to grow. Then go by size, bloom color, water and sun needs, maybe overall care (like deadheading) and your general reaction to the plant. There’s nothing wrong with choosing two of the same plant if you love it. Repetition can be just as attractive in a xeric landscape as complementing textures and colors!
dianthus perennial

This Dianthus next to our bird fountain needs little care and no supplemental watering, but comes back each year. In fact, a new plant showed up in another bed about 15 feet from this one.

  • Buy seeds instead of annual plants. This early in the year, at least in most zones, you still can have plenty of success with seeds for annuals to complement your perennials. There are tons of great xeric wildflower choices that grow from seeds, saving you lots of money. Instead of buying several six-packs of petunias or marigolds, pick up a seed packet of cosmos, zinnias, poppies or a native wildflower mix. Seeds need more attention and watering at first, but the flowers usually reseed for several years. And even though seeds in packet eventually expire, we’ve had success with old flower seeds.
blue flax

I can see this stunning blue flax (Linum lewisii) from my office. The damp spot on the ground is an area of red flax seeds we sowed.

Of course, if you can go big, do it. There are plenty of professionals, books and sites dedicated to xeric landscaping.

How To Water Mature Trees

When drought strikes, it’s tempting to cut back on watering of established trees or stop watering altogether. And maybe water restrictions in your area force your hand. I hate to see it happen, because trees can offer many benefits – most notably shade for homes to cut down on energy use, and shade for other plants to keep them alive and in need of less water. Of course, you can’t beat the enjoyment of sitting under the shade of your favorite tree. I won’t even get into how depressing it is to see dying trees in front lawns…

Ideally, your lawn has only native trees, and especially xeric varieties. In that case, the trees adapt to conditions more easily. Some survive on rainwater alone, but most need a deep watering about once a month during the heat of summer.

desert willow tree xeric

The desert willow (Chilopsis linearis) is a perfect xeric tree for warm to hot desert climates. This one is from a Tucson, Arix., garden.

To water your a mature tree that requires irrigation, avoid a common mistake — watering only near the trunk. Trees do not have tap roots, but instead have a root system that extends out from the tree, more or less mirroring and extending just past, the tree’s branches above. So, when you set out your hose or set up a drip or soaker system, begin near the trunk, and then work your way out to the edges of the tree’s canopy. Scroll down in this handout on caring for trees from Colorado State University for a photo of a soaker hose layout.

To water deeply, you have to water slowly. That means setting your hose or irrigation system to deliver the water at a lower rate for a longer period of time. To reach the roots, the water needs to penetrate the ground to at least 12 inches. If you’ve ever seen roots growing at ground level, they’re probably doing so because the tree is receiving too little or too shallow watering.

Don’t dig a hole around the tree to help get water to go down deeper. The hole allows air in and dries out roots!

If possible, avoid using a sprinkler to water trees. In addition to producing shallower roots, the sprinkler wastes water by dispersing it into the air, where it evaporates. And some trees are subject to leaf diseases from constant watering. The only time I ever spray a tree or bush is if it has aphids, and I give it a fine-water spray in early morning to wash the aphids off.

If you can’t reach a tree with your hose, you can drill a few holes in a 5-gallon bucket and carry it out to your tree. The water will flow more slowly through the hole than if you pour the water on the ground. Move the bucket out and around the tree’s base with each refill.

apple tree along river.

This apple tree is hard to reach with the hose, but we don’t water it because it is along the river bank and the roots take up plenty of water. This year, it had twice as many blooms and may give us some fruit. Trees can help preserve water sheds.

If you want to save tap or well water, reuse! Direct roof water to a tree using the downspout and a dry river bed. Save shower water in 5-gallon buckets (with no holes – you have to get them outside!) but only use the water that flows while the shower warms up, not any soapy flow.

If you have other clear water to dispose, such as kid or dog pools, empty the water onto tree roots instead of a random place in the yard.

Another Reason to Plant Natives: No Soil Amendment Needed

Where I live in New Mexico, the soil is more alkaline than acidic. That means I might as well forget ever trying to grow blueberries, but asparagus is a great choice. We even found some old or wild stalks along our ditch bank last year.

And a soil’s pH balance is just one consideration. Soil texture and drainage are especially important to a plant’s success in a vegetable, herb or ornamental garden. If we didn’t add some organic matter to our vegetable garden each year, the soil would compact from foot traffic and lose nutrients from its work feeding plants. So each year, we work the soil with mushroom compost to keep it rich, water absorbent and well draining.

amended soil for vegetables and herbs

This is part of our ornamental garden, amended with organic matter to grow edibles this year.

Native plants

I couldn’t – and wouldn’t – rework my ornamental garden soil each year. For one, it would be nuts to dig up perennial plants! So gardeners often are advised to add a little bit of compost to the hole dug for a new tree, bush or flowering plant. The compost enriches the soil around the roots, and as long as you water as suggested in the first year or so of more rapid growth and root set, the plant should thrive. But what happens as the plant grows beyond your amendment, especially if you put in a rapidly growing shrub or tree? Eventually, the roots work their way into the soil you haven’t amended. If the soil is so poor or compacted that the roots can’t break through or thrive, the plant could be stressed at the least.

If you choose a native plant, especially for a xeric garden, it’s likely that you won’t have to amend the soil at all. A plant that is adapted to your area’s typical soil makeup will do better if you just loosen the soil around it, usually to an area at least three times larger than the root ball. No need to add anything.

chocolate flower in New Mexico rock garden

The chocolate flower (Berlandiera lyrata) is a native to our region. It crops up from seed around our garden and lawn. And yes, the blooms smell like chocolate! That’s a rosemary in the right foreground.

If plant instructions, or one article or expert tell you to add to the soil, it helps to verify the information with another source. That’s especially true if installing a native plant in your xeric garden. And it’s even truer depending on the first source of advice. There are plenty of reputable sources, and then there are myths, many of which can be perpetuated by those who stand to profit.

lavender in rocky soil

We placed several lavender plants in one of our beds, and maybe should have tested the soil first. Lavender is native to the Mediterranean, where the soil is rocky and alkaline. So it grows well here, but this soil had compacted more than we realized.That and some some cool, wet weather gave our plants a rocky start! Lesson learned.

When amending

It’s also good to check local sources when amending soil. For example, you might hear that adding sand improves drainage, but if you add too little sand, or add sand to clay soil, you can make matters worse, and your soil sets up like concrete. Oh, those poor plant roots…

Most organic matter is good for soil, but plenty of myths abound there as well. For example, manure needs to cook down or compost with brown materials before throwing it on your vegetables. Wood ash is often touted as an amendment, but not in New Mexico, where the soil already is alkaline. Wood ashes also are high in salt. I talked about Epsom salts in a previous post. The bottom line? Get local advice from a few good sources, and if you go with native xeric selections, you probably won’t have to amend the soil unless you have a severely compacted or poorly draining area.

 

Low-water Plants that Hummingbirds Love

As soon as hummingbirds start buzzing around the garden, many locals put out their feeders. I have tried one this year, only because I had few plants blooming when the hummers arrived. I prefer to feed the hummingbirds with natural plants because of time, mess and the fact that native plants seem healthier for the birds and way more fun for us!

hummingbird on agastache

Hummingbird on agastache in our garden in 2013. Photo by David Higgins.

There are many rules about hummingbird food safety, and I worry I will forget, be gone, etc. But there are so many plants hummingbirds love that we already have in our garden or can add to attract more birds. We especially love to watch the male hummers’ courtship dives from our back patio, and I am certain that a few male birds have claimed our rock garden, or some portion of it, as their territory each summer.

To naturally attract hummingbirds and enjoy the same plants they use as nourishment, choose plants with brightly colored and tubular flowers. Hummingbirds are attracted by color, not scent. Red is their favorite, but purple, yellow, orange and pink also bring them to plants. And in addition to tubular flowers, try plants with blooms that nod, or bend downward slightly. Of course, continuous blooming also helps.

Here are a few xeric hummingbird favorites:

Agastache (Agastache cana). This xeric rare wildflower has bright pink flowers on upright stems all summer, and some, such as Texas hummingbird mint, are aromatic as a bonus for humans. There are other many variations of agastache, also called hyssop, in varying purples, oranges, pinks and reds, that attract hummingbirds with their slender, tubular flowers.

agastache cana

Agasatache cana Sinning, also called Sunset Sonora Hyssop is a compact Agastache cana from Plant Select. Image is by Diana Reavis and from Plant Select.

Butterfly bush (Buddleia). Butterflies share this purple-flowered favorite with hummingbirds. The spiked flowers appear at the end of the branches and can be from eight to more than 12 inches long.

Autumn or cherry sage (Salvia gregii). The salvia has bright pink, raspberry-colored flowers on a low bush all summer long. The low- to medium- water plant can grow in nearly any soil.

salvia gregii

Two cherry or autumn sages in a rock garden, just coming into bloom. Hummingbirds love the bright pink flowers.

Desert willow (Chilopsis linearis). This is the tree I miss the most since moving to a colder zone, although I might try it here soon. The beautiful xeric tree can be trained to grow wild and bushy or more tree-like. But its charm to hummingbirds and humans is the large tubular flowers that come in light and dark pink colors.

desert willow flowers

Hummingbirds love the orchid-like flowers of the xeric Desert willow, or Chilopsis. Image by R.A. Howard © Smithsonian Institution, Richard A. Howard Photograph Collection.

Other hummingbird favorites that might grow in the mountains, high deserts and xeric landscape that attract hummingbirds are some types of columbine, some bulbs, such as Crocosmia, and every variety of penstemon. And I imagine you can’t go wrong with a plant I have never tried, but is aptly named “Hummingbird Plant” (Zauschneria Californica), a medium-water, full-sun plant that has scarlet-orange flowers. It will require extra watering for a year or two until established, but grows to more than two feet in height.

Favorite Xeric Plant: Ornamental Grass

When xeriscaping, you can add plenty of interest with varied textures and heights by including a few ornamental grasses in your landscape. We’re always tempted to think first about flower color, but less about interesting foliage. Placing a few ornamental grasses in a xeric landscape or container can add nearly as much impact as a pop of purple with less watering and maintenance.

Choose an ornamental grass that is native to your area, or a similar climate or condition, in place of a shrub or perennial flower. One of my favorite features of grasses is that they can grow tall and move in the wind. In containers, they often add height or contrast to draping and flowering annuals. Warm-season grasses seed out and provide winter interest, even if the foliage browns. They need shearing once a year in spring, a little water to jumpstart growth, and they’re off. If you choose one that’s not native to your area, such as the big-box store selection I found for my containers, make sure it can at least survive with less water or other conditions that differ. You might not get flowers or as much growth, but the grass will survive at least for the summer.

rush grass in container

I like to place ornamental grasses in container arrangements to add height and texture. This juncus is all I need to add interest to a petunia mix and continuity between the pots.

Another benefit of ornamental grasses is that they can serve practical purposes in a garden. Use them for erosion control by placing a small grouping at the bottom of a slope or terrace – and go for a medium-water selection such as Feather reed grass “Karl Foerster” (Calamagrostis arundinacea) here, since the rain or irrigation run-off from above supplies the extra water the plant requires.

feather reed grass

Karl Foerster feather reed grass that was planted a few weeks ago in our rock garden . It already looks great, but will add feathery blooms in summer. It should survive our winter (zones 5 and 6).

Other great locations for grasses are along steps, pathways or corners, in front of dark walls or fences, and anywhere they will catch sunlight and breezes.

Sedges, rushes and some hardy bamboos also fall into the ornamental grass category when landscaping. Just be sure to check the zone, native location of the plant, and especially the sun and water requirements before planting the grass. Some actually do better in marshes – not a good choice for xeriscaping!

Easy care

Grasses are among the easiest xeric plants you can have in your garden. They’re mostly free of pests and diseases. And although I love ornamental grasses, I have seen some gardens with only grasses and gravel. I think you need one or two other xeric plants to break up the look, but I’m not a professional landscaper. To my eye, just gravel and grass in a garden screams “dry!” It’ so easy to complement a low-water grass with a salvia, penstemon or gayfeather.

Some cool-season grasses bolt in the heat, but trimming off their seedheads can rejuvenate the plant, much like clipping off flowers of herbs to force growth back into leaves. Most ornamental grasses are warm-season selections, best planted in the spring. They need a little more water, up to once a week for xeric choices, for the first month or two. After that, water deeply only every few weeks or once a month in the hottest summer weeks. Some will spread, and it’s best to try to divide or dig up unwanted volunteers before they clump too tightly. Other than that, just cut back as directed. Allowing several grasses to overseed in winter could add to your fire hazard, so keep that in mind if you have them near your home or a commercial building.

big bluestem grass before strawbale wall

Newly constructed strawbale wall with xeric plantings. The big bluestem grass on the right foreground got much taller and flowered (see below).

A few xeric grasses

Silky threadgrass (Stipa tennuifolia). This hardy grass grows in all types of soil, uses little water, and loves full sun. That’s a bonus, since the silky seedheads reflect sunlight as they sway in the breeze. One caution for silky threadgrass is its high potential to reseed. That’s a plus in an untamed garden, but not in a more formal xeric landscape.

Big bluestem (Andropogon gerardii).  This is one of our personal favorites. It can reach heights of four to five feet in summer, when it also rewards you with purplish flower spikes that emerge between the beautiful greenish-blue leaves. Some selections require more water than others, so check with the nursery or on the tag for details. Some are highly drought tolerant and thrive down to zone 4.

big bluestem flower heads

The flower stalks of big bluestem grass are purplish, contrasting well with the greenish-blue leaves.

Dwarf fountain grass (Pennisteum alopecuroides). Purple fountain grass (P. setaceum) is a particular favorite of these dwarf varieties, but only makes it as an annual in our zones (5 through 7). Others fare better, although an unusually cold winter could kill them. Most have bright green foliage with bottlebrush flowers. Examples are “Hamelin,” a compact, mounding variety with ivory and gold flowers and “Moudry,” which has brownish-black flowers. One caution: You might have to protect dwarf fountain grasses from rabbits if they visit your xeric garden.

Favorite Xeric Plant: Penstemon

The hummingbirds are swooping around the garden, and soon they will enjoy feeding off several water-wise Penstemon species. The penstemon, also called beardtongue, is a versatile low-water native plant in New Mexico and the Southwest.

In fact, penstemon does best with no added water at all. And the plants can thrive in full sun or light shade. Penstemon comes in a variety of sizes, shapes and bloom colors. But they have in common a slender trumpet-shaped flower that hummingbirds love.

purple penstemon

Hummingbirds love penstemon flowers, but can you also spot the bees in this photo?

Caring for penstemon

Penstemons usually prefer somewhat sandy or clay soil, and don’t need added compost. Most species of penstemon are perennial in our zone (6 to 7), but some are annuals. They’ll bloom from summer to frost. Species such as Arabesque Red bloom from summer through first frost with deadheading. However, if you leave some blooms on the plant, the seedheads ripen and break, which causes the plants to reseed. We’ve had several volunteers come up in our rock garden. And birds love the seeds!

red penstemon AAS regional winner

Arabesque Red was the regional winner (including the Mountain and Southwest regions) fof the All-America Selections in 2014. Photo courtesy of the National Garden Bureau, Inc.

The only way to really harm penstemon is to overwater or overnourish this easy-care plant. Use fine gravel for mulch. Occasionally, aphids gather on the stems, but you can use a fine mist of water to spray them off in the morning and check a few days later.

Penstemon can work well in containers, especially if you select a lower-growing variety. Select low-water companion plants, so that the penstemon does not receive too much water. If it does, it can become leggy. You might find that a penstemon in a clay pot needs occasional watering compared with one in your landscape.

In a xeric landscape

Penstemons are great plants for xeric landscapes. Low growers such as Desert beardtongue (P. pseudospectabilis) spread to about 15 inches wide and 30 inches high, with purple-maroon flowers on stalks above the blue-green foliage. The pineleaf penstemon (P. pinifolius) is a native wildflower with tiny needle-like leaves and bright orange-scarlet flowers. I love watching the hummingbirds maneuver effortlessly into the flowers.

pineleaf penstemon

Our pineleaf penstemon hasn’t flowered yet, but it’s still attractive, with the pine-like foliage and its low spreading nature.

A taller, lankier type such as Rocky Mountain beardtongue (P. strictus) looks gorgeous against a fence, wall or tall rock. Its purple flowers contrast nicely with yellow or white bloomers in the foreground. The bushier pineleaf or Desert beardtongues are perfect to tuck in a corner, or along a step or walkway.

desert beardtongue penstemon

The Desert Beardtongue is a 2015 Plant Select winner. Photo by Bill Adams and courtesy of Plant Select.

No matter which variety of penstemon you choose, you’ll be rewarded by hummingbird guests and the beautiful blooms that appear with very little care on your part!