Not all California native plants go through summer dormancy, but for those that do, it’s a crucial way they survive our long hot and dry season. Just as some plants go dormant and drop leaves in winter, summer dormancy is an adaptation that helps some native plants make it through this time of year.
During this period leaves of summer dormant or semi-dormant plants will shrivel and / or drop, leaving some people to assume plants are dead or severely stressed. However, don’t be fooled—this is a natural process, not a sign of a dead plant! As long as plants are well sited and properly cared for, in most cases, as temperatures cool down these resilient plants will rejuvenate and flourish once more.
In the video below, we’ll help you understand summer dormancy, how it impacts your garden, and provide tips on managing California native plants that experience summer dormancy. Below the video is further information including both a list of common California native plants that will usually go dormant in Southern California gardens as well as a list of common California natives that will reliably remain green or lusher in the summer. If it appeals to you, you can strategically use these “summer green” plants to “balance” how much dormancy you want to appear in your space.
Note: Whether or not plants will look dormant in the summer depends on many factors.
Some native plant species will always remain evergreen or keep leaves through the summer if they are healthy.
Some plant species will always “go dormant,” and some might or might not. Information for each species below will give you a good idea of what to expect.
For plants that might or might not look dormant, how the plant looks in summer will depend on the location of the garden, the soil type, the amount and frequency of water it receives, the amount of sunlight, and other factors such as whether or not it receives “reflected heat” from nearby paved areas or walls.
Use the information below as a general guide for what to expect in summer for some of the more common favorite plants used in California native gardens. Please note that the information below is based on observations of these plants growing in inland valley Southern California gardens such as in Inland Empire, San Gabriel, and San Fernando Valley conditions.
These trends will generally remain consistent for other areas of Southern California and sometimes beyond. However, sites with cooler or more coastal conditions may in some cases experience less dormancy for some of the plants described as going “semi-dormant” in our location.
Common California native garden / landscape plants that should be expected to go dormant or semi-dormant in most gardens in summer:
Most California native sages (Salvia species) – depending on the amount of irrigation, how fast the soil drains, and how much sunlight they receive, different sage species will show different levels of dormancy. Their look may be from “a little less than full” to “looks dead and need to check if it is alive by scraping the bark,” (see our YouTube Summer Dormancy series here). Different species, or the same species in different amounts of sun, may show different levels of dormancy in the same landscape. In full sun in inland conditions, black sage and Winnifred Gillman sage will all reliably be significantly summer dormant. Hummingbird sage will be pretty dormant if it does not receive a deep irrigation at least every other week, but can quickly return with lush new growth in the fall if watered less often. White sage can be expected to look somewhere between significantly and partially summer dormant depending on conditions. If you are not in a wildfire hazard area, leaving the dried seed heads on sages though their dormant period is one way to keep some “ornamental value” until closer to fall regrowth while providing food for birds.
De La Mina Verbena (Verbena lilacina ‘De La Mina’)– often looks almost dead in summer when receiving the typical watering schedule for native gardens (a deep irrigation every 3-4 weeks). Part-shade, afternoon shade, or additional water will keep it greener and flowering longer, if desired.
California Sagebrush (Artemisia californica) – will go somewhat or significantly summer dormant. Popular cultivars ‘Canyon Gray’ and ‘Montara’ usually look less dormant or may remain evergreen depending on watering and sun exposure. These cultivars are usually well adapted to part shade or afternoon shade in inland plantings, and this will also help reduce their dormancy.
Brittlebush (Encelia farinosa) – usually goes semi-dormant in summer, retaining newer leaves and losing older leaves lower on the stems. Additional irrigation may keep the plant looking fuller, but often results in excessive growth that will need to be cut back significantly every fall to keep the plant looking good and blooming well.
California Bush Sunflower (Encelia californica) – usually goes very dormant in Summer once it is established. Often it will look almost dead in inland gardens. For most gardens, we recommend planting the closely related brittlebush instead, though we do grow California Bush Sunflower in our demonstration garden and find it to be absolutely lovely in the spring.
Yarrow (Achillea millefolium) – depending on the amount of water and sun it gets it may remain evergreen or go semi or very dormant. If watered regularly it will remain green but if in all-day full sun will still look wilted in the mid-day summer heat. Once established, it may survive in full sun with very little water but will look dead in the heat of summer then grow back from the base once it cools or is watered. Plants in shade, part shade, or growing in openings between larger shrubs are much more likely to stay more lush looking without requiring extra water beyond the baseline being provided for the rest of the native planting area.
Penstemons (Penstemon species) – Most California native penstemons die back significantly after their flowers set seed. They will look somewhere between semi and fully dormant. Sometimes they may even look partially dead due to brand dieback after flowering, but usually will be revealed as dormant by observing the swollen buds near the base of these stems.
After allowing flowers to dry and set seed and scattering those seeds in the garden, cutting each branch back to just a few stem nodes (stolen areas along the stem) at the base of the plant will usually result in the plant responding with fresh foliage relatively quickly. Alternatively, if you begin to see new growth at the base, often occurring sometime around August, you know it may be time to cut back the older dead and dormant growth.
Finally, in their first year after planting, we recommend that you cut back faded flower stems as soon as the flowers fade and before the seed develops, so the plant uses its energy to become established rather than to ripen seed. Penstemons allowed to set seed in their first year sometimes expend so much energy doing so that they do not live into the next season.
One last note, the popular Margarita BOP penstemon cultivar, and its species, foothill penstemon are a bit of an exception to this. Depending on the amount of sun and irrigation, they may remain evergreen, especially in their first few years. Their pattern of denser branching and general growth means that they are less likely to require that annual cut back. However, also depending on conditions, they may well show die-back after blooming and generally respond well to the hard cut-back as described above, even if that is not provided every year.
As relatively short-lived plants, there is always a chance penstemons will not rebound after being cut back, but this is why we recommend scattering their seeds. Often by the time the original plant dies a few seedlings will have come up, so you can have just as many, or often a few more penstemons over time compared to however many you planted originally.
Red Buckwheat (Eriogonum grande var. rubescens) – Most California buckwheat species are generally considered evergreen and because many bloom in mid-summer and sometimes into fall, using them can be a way to “balance” the look of a garden with summer dormant species. However, if some buckwheat species become very dry, they can allow leaves to wilt or even drop older leaves, becoming semi-dormant or “drought-deciduous” to conserve water.
When located in a garden in full sun, if soils drain quickly and water is provided infrequently, as we recommend for most native plantings, red buckwheat may exhibit some dormancy. In our demonstration garden, we will have some red buckwheat plants remain evergreen and some show these signs of semi-dormancy on their leaves, even while still in bloom.
In some gardens by mid-summer some red buckwheats that receive very-little to no irrigation may look completely dormant / almost dead but may come back with vigor in the fall. This often happens with seedling red buckwheats that have come up spontaneously in parts of a yard and receive no irrigation. Some will re-emerge from dormancy with no problem while some may act more like annual wildflowers and die once they fully dry out.
On the other extreme, even in full sun with reflected heat, red buckwheat can be provided with additional regular water and will usually remain evergreen and bloom longer. On automatic irrigation systems, red buckwheat can usually be grouped with plants receiving more frequent irrigation than most California native gardens receive, up to once per week. Or, in native gardens, if a lusher look is desired than would be possible with the deep waterings every 3-4 weeks that most gardens will receive, supplemental watering with a hose can be provided to the red buckwheats in between the waterings of the full garden as needed. In this situation, watering by hose one time half-way between the “dry period” between full-garden watering is usually sufficient to keep plants looking perkier.
Fragrant Pitcher Sage (Lepechinia fragrans) – usually will go semi-dormant in the summer once it is established. In full sun plantings this usually looks like a bit of wilting over the entire plant with some of the older leaves lower on stems looking a bit “crispy” or burnt. In shadier plantings, including under trees, leaves may look anywhere between “a bit” and “somewhat” wilted and older leaves lower on stems will often fall off. When weather cools in fall, some of the nodes on the lower stems will “break bud” and new fresh leaves will emerge helping to create a “full” look on the plant again. It is normal for a few of the stems to fully die back, so if there are some bare stems still on the plant when the other new growth has emerged, just prune them off. Although it may look wilted, this plant smells absolutely amazing in hot weather and perfumes a larger area of any garden in which it is planted, particularly if it is in the sun.
Blue elderberry (Sambucus mexicana / Sambucus nigra ssp. mexicana) – If in full sun in inland conditions, blue elderberry will usually go somewhere between semi-dormant and significantly dormant. Shade during part of the day helps keep it looking fresher longer. If you are going to plant one, placing it somewhere where a building or large tree will provide afternoon shade to at least part of the canopy will keep it looking lusher even though foliage will still thin and some leaf drop will occur during summer. This is natural. Blue elderberry is a very valuable habitat plant, but it should only be planted by people who can accept a plant as large as this looking somewhat dormant in summer, particularly if it will be located in full sun.
Coyote Mint species (Monardella species) – Plants in more shade or that receive more irrigation will remain evergreen. Plants in more sun that get less water will thin significantly in summer.
Dudleyas (Dudleya species) – These popular native succulents, even when planted correctly need to be allowed to shrivel in the summer and have their older leaves dry out. In most gardens, resist the urge to water them more than once per month in the warm season in as you are more likely to lose them to rot than to lack of water.
Gumplants / Gumweeds (Grindelia species) – These under-utilized perennials bloom and stay green much later into the summer than many native perennials, but after bloom will eventually thin out and should be expected to look semi-dormant to very dormant. Once the flower stems and leaves along them die back, cut back the plant to a few inches tall. New leaves will begin to emerge later in the year.
Engelmann Oak (Quercus engelmanii) – established Engelmann oaks are considered “Drought Deciduous” and may remain evergreen or may begin to drop some or many leaves depending on location and how dry the soil gets. Engelmann oaks in most landscape locations are benefitted by an occasional deep irrigation during the summer (before but not during a heat wave). This can often keep them evergreen. If they drop leaves, do not panic, it does not mean the tree is going to die. Often a deep watering when signs of leaf drop begin (ideally), or after leaves drop (if necessary), will result in a new flush of leaf growth pretty quickly.
Currants (Ribes species – except evergreen currant / Catalina perfume) – Established native currants will usually go summer dormant or semi-dormant, even in shade. Newer foliage may remain green, but it is completely normal for older leaves to yellow, turn somewhat brown, and either drop or persist on the plant for a while. Golden currant, an incredible habitat plant for songbirds and hummingbirds, grows very well in gardens in our area, and likes extra water compared to many popular native garden plant choices. It can tolerate full sun in inland conditions, unlike many other currant selections, but will usually look dead to a casual observer by mid-summer. It is great to use as a background plant so it can look glorious when in bloom, then visually fade away when it drops its leaves. Before leaf drop, an orang-ish fungus that is a type of rust “disease” will normally occur on golden currant plants. While this is categorized as a disease, it is a normal occurrence, and the plants normally leaf back out just fine later in the year. Do not panic, fungicides are not needed. Feel free to rake out the dropped leaves if you are determined to try to reduce its prevalence in your landscape, but most gardeners do not bother.
Canyon Prince Wild Rye (Leymus condensatus ‘Canyon Prince’) – As a “cool season” grass, this plant looks its best in fall through spring, and then often look either looks a bit dry or even quite dry and partially brown as it goes through its natural cycle. Younger plants are less likely to exhibit this semi-dormancy in some gardens. A bit more water will keep plants looking fresher longer in some gardens, but if too much water is applied, they will flop over and kind of look like someone sat on them. A hard cut back in the fall just before or after new growth begins keeps Canyon Prince wild rye looking good in the rest of its prime growing season.
Silver Carpet Aster (Lessingia filanginifolia ‘Silver Carpet’ / Corethrogyne filanginifolia ‘Silver Carpet) – is more likely to remain evergreen when grown in dappled shade or when in afternoon shade. This is often easy to provide if it is being used as a ground cover around taller plants. If in full sun, it will likely look very dormant by mid-summer, but can still be a lovely plant during the rest of the year.
Favorite plants that remain green or flower in summer and can be used to “visually balance” the look summer dormant plants in a garden (if you care about that):
- Toyon (Heteromeles arbutifolia)
- Hollyleaf Cherry (Prunus ilicifolia ssp. ilicifolia)
- Catalina Cherry (Prunus ilicifolia ssp. lyonii)
- Lemonade Berry (Rhus integrifolia)
- Sugar Bush (Rhus ovata)
- Manzanitas (we recommend Sunset, Howard McMinn, Byrd Hill, and Dr. Hurd at top choices) (Manzanita species)
- Desert Willow (Chilopsis linearis) – blooms all summer in most Southern California gardens
- Most Buckwheats (Eriogonum species) including California Buckwheat, Santa Cruz Island Buckwheat, and Ashy Leaf Buckwheat
- Coyote Brush, including Pigeon Point Coyote Brush (Baccharis pilularis and Baccharis pilularis ‘Pigeon Point’)
- Coffeeberry, including Eve Case Coffeeberry (Frangula californica / Rhamnus californica and Frangula californica ‘Eve Case’ / Rhamnus californica ‘Eve Case’) – technically evergreen, though in summer heat if it is in full sun, Coffeeberries drop older leaves and look sparser than during the rest of the year. This can be tamped down on by watering a bit more.
- Baja Fairyduster (Calliandra californica)
- Bladderpod (Isomeris arborea / Peritoma arborea)
- Deergrass (Mulhenbergia rigens)
- Coast Live Oak (Quercus agrifolia)
- Catalina Perfume (Ribes viburnifolium) – needs full shade
- Oregon Grape and Creeping Oregon Grape (Berberis aquifolium and Berberis repens)
- Clustered Field Sedge (Carex praegracilis) and California Meadow Sedge (Carex pansa) meadow plantings – can go dormant if not watered sufficiently for their conditions. Will need medium water if in full sun but remains remarkably low water demanding to stay green if in part shade or shade.
- California Goldenrod (Solidago velutina ssp. californica)- can spread aggressively in the garden and can cause distress for people with seasonal allergy issues. However, it remains vibrant and blooms in the mid-summer and into fall when many of the other perennial plants have concluded. Because it blooms in this season it is important pollinator plant for a time of year that often has fewer common native plants used in gardens blooming. It will then go somewhat deciduous in the winter and remains looking best when cut back hard to remove the old flowering stocks prior to new spring growth.
