Quick Facts...
- A xeriscape is a water-conserving landscape design.
- Flowers add color to xeriscape yards and Gardens.
- Improve soils before planting most flowers.
- Soil improvement is easier if only annual flowers are used for the first year or two.
- Plant flowers according to site exposure.
- Spring-flowering bulbs are drought-evaders and make good flowers for a xeriscape.
Garden flowers provide showy, colorful displays in a xeriscape Garden. Xeriscape (zer-i-skap) is a water-conserving landscape. Annuals and perennials can be integrated with shrub borders and groups of trees, or they may be planted in their own beds along fences, walls, walks and patios.
Soil Conditions and Exposure
Before selecting Garden flowers, check your soil. Most flowers do poorly in heavy clay, due to lack of oxygen to their roots. Sandy soils may have poor water-holding capacity and be low in available minerals. If either extreme is true in your yard, do not plant perennial flowers the first year or two.
Improve the soil with sphagnum peat or compost, available in bales or bags at Garden centers. Incorporate 1 cubic foot of sphagnum or compost per 8- by 10-foot area to a depth of 9 inches. Plant only annuals so it will be easier to cultivate and incorporate additional organic matter in the fall, after the plants are killed by frost. Add more sphagnum or compost each year until the soil is easily worked and does not compact. Perennial flowers may then be planted.
Select plants that are compatible with the exposure. For north sides of structures or among shrubs, choose plants that tolerate less sun. For example, perennials for a shaded spot might include canterbury bells, primrose and violets. Such plants usually need cool, more consistently moist soils than most Garden flowers. They can, nevertheless, be useful in the shaded parts of a xeriscape. Add organic mulches such as wood chips to reduce watering frequency.
Bulbs
Most bulbs do best in full sun, but they must have well-drained soils. Spring-flowering bulbs are well-suited for xeriscape plantings because they are drought-evaders. That is, they grow in the cooler, more moist spring and fall seasons and lie dormant underground during the hot summer months.
Use tulips, grape hyacinths, hyacinths, daffodils and crocus for naturalizing a xeriscape. In fall, plant spring-blooming bulbs in the areas you want them. For more information on bulbs, refer to fact sheets 7.410, Fall-Planted Bulbs and Corms, and 7.411, Spring-Planted Bulbs, Corms and Roots.
Annuals
Almost all annuals commonly sold do well in xeriscape Gardens with some soil preparation and no more than one good watering a week (1 to 2 inches). For hot, dry exposures, the most reliable include marigolds, zinnias, cockscomb, sweet alyssum and bachelor's button. Where soils are shaded and cooler, use annuals such as lobelia, pansy and forget-me-not.
Rock Gardens
Rock Gardens can be an attractive addition to a xeriscape Garden. Put them in logical areas such as steep sunny slopes, rather than as mounds in the middle of a yard. Strive for a natural look and avoid a "rock pile" look or "Garden of rock" look. For more information on rock Gardens and the plants to use, refer to 7.401, Rock Garden Plants.
| Table 1: Perennial plants for shady spots. |
| Plant Name | Flower Color | Flowering Time | Height (ft) | Remarks |
Aconitum napellus Monkshood | Purple | June- Sept. | 3 to 4 | Use in dense shade. |
Anchusa azurea Anchusa (Italian bugloss) |
Deep blue | June-July | 3 to 5 | Tall accent. |
Aquilegia spp. Columbine | White, blue, pink, yellow | May-June | 1 to 2 | Use with shrubs. |
Campanula medium Canterbury bells |
Pink, purple, white | June-July |
3 | Tall accent. |
Campanula spp. Harebell | Blue, white | June- Oct. | 1 |
Useful edging. |
Dicentra spectabilis Bleeding heart | Deep pink | April-June | 1 1/2 | Use with shrubs, north sides. |
Dictamnus albus Gas plant | White, pink | June-July | 2 to 3 | Use with shrubs. |
Iberis sempervirens Candytuft | White | April-June | 1 | Foliage evergreen. |
Lobelia cardinalis Cardinal flower | Bright red | July- Sept. | 2 | Use in dense shade. |
Physostegia virginiana Dragonhead (false) | Lavender, white | Aug.- Sept. | 3 to 3 1/2 | Aggressive creeper. |
Primula spp. Primrose | Yellow, red, blue | April-May | 1/2 | Showy spring flowers. |
Thermopsis rhombifolia Golden banner, false lupine | Yellow | May | 1 to 2 | Aggressive creeper. |
Viola cornuta Horned violet, viola | Various | May- Sept. | 1/2 | Shade or sun. |
Viola odorata Sweet violet | White, purple | April-May | 1/2 | Aggressive creeper. |
| Table 2: Perennials for sunny spots. |
| Plant Name | Flower Color | Flowering Time | Height (ft) | Remarks |
*Achillea spp. Yarrow | Yellow, white, pink | July- Sept. | 1 to 3 | Adapts to very poor soils; fern-like, aromatic foliage. |
*Armeria maritima Thrift | Pink | May-Aug. | 1 | Grass-like foliage. |
*Asclepias tuberosa Butterfly weed | Orange | July-Aug. | 1 to 1 1/2 | Grows in poor soils; very deep-rooted. |
Aster novae-angliae Aster (New England) | Purple, white | Sept. | 3 to 5 | Showy for fall. |
Aurinia saxatilis Basket-of-gold | Yellow | April | 1 | Reseeds readily. |
*Cactus (various plant groups) Cactus | Various | May-Aug. | Various | Use in sandy soils. |
*Centaurea cyanus Cornflower | Blue, white | May- Sept. | 2 | Border plant, cut flower. |
*Coreopsis lanceolata Coreopsis | Yellow | June-Aug. | 3 | Easy to grow in most soils. |
Delphinium hybrids Delphinium | White, purple, blue | June-July | 4 to 6 | Tall accent; may need staking. |
Dendranthema coccineum Painted daisy | White, pink | May-July | 2 to 3 | Showy, cut flower. |
Dianthus barbatus Sweet William | White, pink, red | May | 2 | Aggressive biennial. |
*Echinacea purpurea Purple coneflower | Yellow, purple | Aug.- Sept. | 4 to 6 | For tall background. |
*Eriogonum umbellatum Sulphur flower |
Yellow | May-June | 1/2 | Grows in poor soils. |
*Gaillardia aristata Gaillardia, blanket flower | Red-orange | June- Sept. | 2 | One of the best for xeriscapes. |
Gypsophila paniculata Baby's breath | White | July- Sept. | 2 1/2 | Lacy, bush-like. |
Hemerocallis spp. Daylily | Yellow, red, orange | June-July | 2 to 2 1/2 | Spreads to large clumps. |
*Iris hybrids Bearded iris | Various | May-June | 1/2 to 3 | Easy to grow. |
*Lavandula angustifolia Lavender | Lavender | July-Aug. | 1 | Fragrant; shrub-like. |
Leucanthemum x superbum Shasta daisy | White | July-Aug. | 2 to 2 1/2 | Useful with shrubs. |
*Liatris scariosa Gayfeather | Lavender | July- Sept. | 1 to 2 | Showy in late summer. |
*Linum perenne Blue flax | Blue | May- Sept. | 1 1/2 | Almost shrub-like. |
Lupinus polyphyllus Lupine | Various | June-Aug. | 2 1/2 to 3 | Good accent with shrubs. |
Monarda didyma Beebalm | Red, pink, violet, white | June-July | 2 to 3 | Best in mass plantings. |
Paeonia hybrids Peony | White, pink, red | May-June | 2 to 2 1/2 | Tolerates some shade. |
*Papaver nudicaule Iceland poppy | Orange, reds, white, pinks | April-June | 1 | Good edging plant. |
*P. orientale Oriental poppy | Orange, salmon, red | May-June | 1 1/2 to 2 | Aggressive creeper. |
*Penstemon spp. Penstemon | Red, white, blue | June-July | 2 to 3 | Many varieties. |
Phlox paniculata Garden phlox | White, lavender, pink | May-July | 1 to 1 1/2 |
Easy to grow. |
*Rudbeckia hirta Black-eyed Susan | Yellow | July | 2 to 3 |
Needs space. |
*Rudbeckia laciniata 'Hortensiana' Golden glow | Yellow | July- Sept. | 5 to 6 | Tall, late summer flower. |
*Scabiosa caucasia Pincushion flower | Lavender | May-Aug. | 1 to 1 1/2 | Fern-like foliage. |
*Sedum spp. Sedum, stonecrop | Various | May- Sept. | 1/2 to 1 | Many varieties; succulent foliage. |
Veronica spicata Veronica | Purple |
May-June | 2 to 4 | Aggressive creeper. |
Viola cornuta Horned violet, viola | Various | May- Sept. | 1/2 | Shade or sun. |
*Zinnia grandiflora Paperflower | Yellow | June- Sept. | 1/2 | Long-lasting bloom. |
| *Most drought-enduring. |
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