How to Create a Xeriscape Container Garden
Xeriscape container gardens bring all the rewards of a diverse display with the value of conserving water and resources. Less maintenance and daily watering mean more time to enjoy the show. Join gardening expert Katherine Rowe in exploring the components of a successful waterwise potted arrangement, adaptable to any scale.
Contents
Creating a waterwise landscape doesn’t have to end with rock gardens or gravel beds. If you want to enrich a space with plants but without the demand for daily water, a xeriscape container garden is a water-conserving method.
Xeriscaping is landscaping that involves little, if any, supplemental irrigation. It involves choosing the best plants for the site, including natives, with good drought resistance. For xeriscape container gardens, special consideration goes into siting, container selection, and potting formulas. The result is a bountiful planting arrangement with varying forms, flowers, and foliage.
There are several reasons to choose xeriscaping as a theme for container selections, with the clear advantage being thoughtful water usage. Many of us live in areas where water conservation is a necessity, especially in dry summers. Choosing the right plant, site, and pot can help reduce water use.
Pots also expand the realm of gardening in small spaces, such as patios and balconies. And, watering is intensive. If you travel often or aren’t able to water regularly, a xeric setup becomes more viable and requires less maintenance.
Xeriscape container gardens are an opportunity to be creative with planting arrangements, from attracting pollinators to playing with color. Water efficiency doesn’t limit us only to cacti. A diversity of forms and colors brings life to the space. Choosing selections that require little supplemental water is the key component.
Xeric Container Culture
Due to their limited volume and above-ground siting, containers dry out more quickly than in-ground plantings. They lack the surrounding soil mass and the insulation and moisture retention it provides. They also have more direct exposure to air temperature, drying winds, freeze/thaw cycles, and other elements.
Containers, then, need water more often than those in the garden bed. Depending on your climate, rainfall may be enough to sustain the collection (that’s the aim). But with fluctuating seasonal conditions, container specimens will show stress before their in-ground counterparts without water for a prolonged period. Plan for some watering, especially as young plants establish their root systems. Sturdy roots are the key to their survival in varied conditions.
Potted specimens must also be hardy (extra hardy) to perennialize. If you plan to overwinter your containers outdoors, choose plants that are two zones hardier than your USDA growing zone. If you live in zone 7, a perennial that survives winter in zone 5 is likely to overwinter successfully in your pot.
Siting
Before we select our plants, considering site conditions helps guide the best picks. The first step is to note how the sun moves through the site. If you’re working with full sun exposure (six or more hours daily), you have lots of specimen options, but the heat and direct light also increase water loss. Place the most durable xerophytes in the sunniest parts of the site. Partial shade (four or more hours of sun) and especially protection from intense afternoon rays can reduce moisture loss.
Xeriscape container gardens are sometimes subject to reflective light and heat from paved surfaces and walls. These can be drying in all-day sun exposure. Strategically placing trellises, arbors, and shade structures, or using trees, can help filter sunlight at its most intense. Walls can also reduce cooling air circulation around the specimens. Allow a little space between structures and each other in a cluster.
Pot Size and Material
When it comes to pot selection, size and drainage capacity are the key elements. Large pots and their greater volume allow room to accommodate mature roots and upper growth. They also retain moisture longer than small pots and overwinter better.
Opt for containers with good drainage, as well-draining situations are essential for most drought-resistant selections. They don’t thrive in standing water, which depletes oxygen levels in the soil (necessary for roots to function).
Terra cotta and porous materials allow good aeration and drainage, which promotes healthy roots. They also dry out faster, require more frequent watering, and may crack in freezing temperatures without protection. Glazed ceramics, metal, and plastic hold moisture longer.
Potting Soil
To give the xeric container garden the best foundation, use a high-quality, well-draining potting mix. Formulated for contained growing, pre-packaged potting mixes are sterile, contain nutrients to foster growth, and have moisture-retaining properties in combination with good drainage. They’ll usually have perlite, vermiculite, or other inorganic soil conditioners to boost drainage and moisture retention.
Avoid “garden soil” tailored for in-ground plantings. Potting mix is airy and less compact, allowing roots to breathe under less dense conditions. You can also use formulas suited for specific selections, like cacti and succulent mixes.
Moisture-added soils that contain hydrogels hold water and release it slowly into the surrounding soil. Added moisture may benefit perennials and annuals that prefer evenly moist soils. Other xeric and rugged perennials prefer soils to dry out between sessions, at least slightly, and retentive mixes may hold too much moisture.
Amend with compost at planting and topdress each spring to improve drainage and nutrition, but keep organic richness in mind. Many xeric perennials prefer average or lean soils and don’t need the extra nutrition. Mycorrhizal fungi added to planters may improve resiliency as they benefit moisture and nutrition uptake for the roots. Available commercially, add them to the soil at planting time.
Consider Drip Irrigation
Even though we’re reducing the need to water, easy access to a supply source makes it more efficient when necessary. At each session, water deeply until it flows out of the base. If you’re using a multitude of pots for your xeriscape container garden, a simple drip system helps control water volume for plants with similar growing requirements.
Drip irrigation reduces runoff and is low-volume. It allows concentrated delivery directly to the roots. Positioning the drip at the base of the plant ensures root contact to minimize evaporation. It also avoids splashing the leaves and creating favorable conditions for fungi. Set irrigation on a timer for controlled watering for specimens that prefer the same moisture requirements.
Choosing Xeric and Drought-Resistant Plants
Our plant selection will vary by our growing areas and microclimates. Dry, hot climates need the most xerophytes, while more temperate zones can incorporate drought-tolerant selections. Xerophytic plants are those adapted to grow in dry, arid environments with a limited water supply (or limited access to fresh water, like a salt marsh or bog). They have physiological adaptations to store water, reflect heat, and conserve energy.
Drought-resistant plants store enough water to withstand dry spells. With long, fleshy taproots, water-filled stems, or slowed processes, they create reserves until water is available.
In looking for xeric and drought-resistant plants, leaves are a good indicator. Silvery, fuzzy, or coated leaves are a means of natural sunscreen, cooling, and water retention. They reflect sunlight, reducing water loss through transpiration. Thick, succulent leaves and stems indicate water stores to support growth in dry climates.
Diverse Options
Xeric container gardens brim with biodiversity. A diverse arrangement offers benefits like nectar and pollen-rich blooms for pollinator resources, natural pest control through attracting beneficial insects, and an inventive display.
A diversity of foliage and forms brings visual interest. Cluster pots and group arrangements with varying leaf shapes, staggered blooming, and heights. If you’ve got the space and large enough pots, include drought-tolerant trees and shrubs to join their lower-growing perennial and annual companions. Some species and their cultivars perform well in xeric container culture as compact or dwarf varieties.
Xeric Perennials
| Aloe spp. | Aloe |
| Agave spp. | Agave |
| Aeonium spp. | Aeonium |
| Sedum spp. | Sedum |
| Santolina chamaecyparissus | Lavender Cotton |
| Yucca spp. | Yucca |
Drought-Tolerant Perennials
| Echinacea purpurea | Coneflower |
| Asclepias tuberosa | Butterfly Weed |
| Eryngium spp. | Sea Holly |
| Echinops spp. | Globe Thistle |
| Linum perenne | Flax |
| Achillea millefolium | Yarrow |
| Salvia leucantha | Mexican Bush Sage |
Drought-Tolerant Annuals
| Lantana spp. | Lantana |
| Pelargonium spp. | Scented Geranium |
| Catharanthus roseus | Vinca |
| Melampodium divaricatum | Melampodium |
| Zinnia angustifolia | Mexican Zinnia |
| Bougainvillea spp. | Bougainvillea |
Rely on Natives
Native plants, especially those that occur naturally in the driest areas of our growing environments, are less likely to need supplemental water in pots. Natives have a specific set of attributes acclimated to the locale, requiring few extra resources. Native perennials bring years of recurrent color, even in a xeric container garden.
Arrange by Cultural Preferences
An essential part of maintaining and sustaining a flourishing waterwise container garden is to meet the proper growing conditions of all the selections. Streamline care and promote the best health by grouping like selections in the same pot or site. Succulents and xeric types need less water than annuals, for example. Keep like-types together, paying special attention to sun exposure and heat tolerance.
Mulch
Mulch is a valuable resource not only in the garden bed but in pots, too. Topdress with a two to three-inch layer to regulate soil temperatures and retain moisture. It adds nutrients as it decomposes, and it keeps the soil surface from drying (making water delivery and uptake efficient).
Dark mulches reduce reflectivity, heat effects, and evaporation. White pebbles and sand that we associate with low-water gardens can increase the reflectivity in the immediate area. Good mulch materials for xeric situations include bark and aged woodchips, compost, pine straw, and leaves.
Maintenance
Part of xeriscape container gardening and its reduced maintenance includes holding back on fertilizing. Fertilizer stimulates quick flushes of growth, which require water. Natives and other durable selections won’t need the added nutrition to grow and flower, at least as long as the potting soil is meeting their needs. Plan to refresh aged potting mix, which becomes compacted over time and depleted of nutrients, every few years (depending on the selection and size) or as you see signs of decline.
Pruning, too, takes a break on potted xeriscapes. Other than removing brown or declining parts, there’s no need to encourage new growth through severe trimming. If you need to prune to manage size, do so at the least stressful time (usually spring or fall) for the plant to recover. Plan to water more as it flushes.
If you’re working with perennials, overwinter them in their pots for reemergence in the spring. Tender tropicals and some annuals, too, overwinter in a sheltered spot. There are several ways to overwinter perennials in pots and containers, from clustering them to adding insulation.
