x Halimiocistus

( hal - im - ee - oh - SISS - tuss )

At-A-Glance Information

This genus of hybrid evergreen shrubs native to Portugal and France inlcudes cultivars which need full sun and little to no water, making them great candidates for water-wise gardens. They are dense, mound-forming plants that are genetic crosses between Cistus salviifolius and Halimium, valued for their handsome foliage, profuse blooms, and high tolerance for both sun and heat. These are great in rock gardens, on dry banks, and for spilling over walls.

x halimiocistus Species and Varietals

This hybrid genus of plants is a member of the Cistaceae plant family, and is related to Helianthemum and Cistus. The ideal growing zones for x Halimiocistus are USDA hardiness zones 7-10 or Sunset growing zones 4-24. To find your zone, click here: Zone Map.

x Halimiocistus sahucii (Sahuc Rock Rose)
This species reaches 2 feet tall and 3-4 feet wide, with narrow leaves in dark green. White flowers bloom profusely in springtime, and have a central puff of yellow stamens. Good for dry banks and rock walls.

x Halimiocistus wintonensis
Reaching 2 feet tall and 4-5 feet wide, this species has furry, greyish-green leaves and produces white flowers with a central band of purple-red. Bloom comes in spring and early summer. Variety 'Merrist Wood Cream' have a red central band and yellow-cream colored petals.

Caring for x halimiocistus

After a few years, these plants will become a bit leggy and unattractive; pruning can solve this issue as a stop-gap, but the plant will eventually have to be replaced. Continually taking and rooting cuttings will provide you with new plants when you need them (see the Propagation section below for more information).

Plant xHalimiocistus shrubs and groundcovers in a space that receives full sun; ideally, they appreciate between 6 and 8 hours of sun each day. When these plants are grown in lower light, they will not flower as profusely and can become leggy. They should be situated in a spot that is sheltered from frost and drying winds. Ensure that soil is well-draining and has a pH of between 6.0 and 7.0 (slightly acidic to neutral). They thrive in somewhat sandy soils. If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly and deeply as they establish a strong root system in their new home; they take about a year to acclimate fully. Once established, they are considered drought-tolerant plants and can get by on rainwater alone for much of the year with supplemental waterings in extended periods of drought.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. After flowers fade, deadhead the plant and prune to form an attractive shape. Pruning is simple; remove any damaged, diseased, or dead foliage at any time during the growing season. Pinch back plants when they are young to encourage a bushier habit. After some time in the ground, these plants will become a bit leggy and unattractive; pruning can solve this issue as a stop-gap, but the plant will eventually have to be replaced. These shrubs can last for 5 to 10 years in the landscape before needing to be replaced, and can easily be propagated through cuttings or seed. For more information on propagating these shrubs, see the Propagation section below.

Growing xHalimiocistus in Containers
xHalimiocistus shrubs are wonderful in the ground, but can also be grown in containers. Dwarf or prostrate cultivars are perfect for container cultivation. Choose a container that is at least a few inches wider and deeper than the nursery pot or root ball. Ensure that the pot has adequate drainage holes on the bottom to allow for excess water to flow away. Fill with a well-draining potting mix amended with organic material and perlite, and top with a layer of mulch to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water regularly as the plant establishes itself in its new home. Once established, waterings can be lessened. These plants, when grown in containers, will need more frequent irrigation than those grown in the ground. As a general rule of thumb, water whenever the top few inches of soil feels dry to the touch. Pinch back young plants to encourage a bushier habit. Prune to remove dead, damaged, or diseased foliage at any time during the growing season. Every few years, check the bottom of the pot to ensure that the plant is not outgrowing its root space. If roots are growing through the drainage holes in the bottom of the container, it is a good indication that it needs to be potted up; choose a slightly larger container and repot.

Propagation

x Halimiocistus can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your shrub, follow the instructions below:

Propagating x Halimiocistus by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. If you don't have any potting medium on hand, you can make some. Just mix together equal parts (by volume) moss peat and horticultural-grade sand or grit sand.
In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6 inch portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new shrub.

Propagating x Halimiocistus by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. Harvest as many as you can, and place them in a paper bag in a dry, cool, dark area. continue to mature and be released. Once released, take them out of the bag and put them in a container to work with them.
Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 7-14 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Problems and Pests

These hybrid plants have few pest or disease issues. For information on commonly encountered pests and diseases in the garden, consult the following pages:

Pests & Pest Management

Plant Issues