Found in a wide variety of the state’s biomes, from grassland to chaparral, geophytes are plants that arise once a year from an underground “storage organ,” such as a bulb, corm, tuber or rhizome. You’d think, given their kaleidoscopic beauty, that every California native garden would be bursting with geophytes, but you’d actually be mistaken. In fact, it isn’t uncommon to find even large-scale native gardens without a single Calochortus, Lilium or Dipterostemon.

“But, how could that possibly be?” you ask, choking back tears.

Well, first of all, a good geophyte can be hard to find. Although the situation has definitely improved, until recently, you’d be lucky to find any bulbs or corms for sale at your local native plant nursery, ever. Even the best and most well-stocked usually have an extremely limited number of geophytes available, and only once a year while the bulbs are dormant. The handful of specialty sites that sell native bulbs online quickly sell out, and if you’re too late, you’ll have to wait an entire year just to try again.

I’m aware that this level of demand would seem to refute my thesis, but it’s really more of a supply issue, an artifact of the time and effort it takes to bring a typical native geophyte from seed to flowering plant. While the most infamous of all may be the gorgeous Spotted Humboldt Lily (Lilium humboldtii ssp. ocellatum), which can take 4-5 years to reach flowering size, propagating nearly all of California’s native geophytes to the point where they can be sold will take at least 2-3 years. That’s a lot of time, labor and resources to invest in something the size of a hazelnut, which also explains why they can be rather pricey – when they’re available at all.

Then, if you actually manage to get your hands on some native bulbs or corms, what the hell are you supposed to do with them?

I’ve noticed that much of the reluctance to garden with geophytes revolves around the question of how deep they should be planted, a metric whose importance has been somewhat exaggerated, in my opinion. After that, questions about placement, exposure, watering and protection from predators (like rodents) appear to overwhelm even seasoned native gardeners; so much so, in fact, that they lose their nerve.

Finally, geophytes may just represent a bridge too far for the “I Am Embarrassed by Summer Dormancy” cohort of California native gardeners. And yes, it’s simply a fact that your garden’s shimmering field of Common Goldenstar (Bloomeria crocea) in spring will wither away by summer, leaving a patch of bare ground with nothing to catch your eye but their wispy remains. (Geophytes aren’t classified as “Spring Ephemerals” for nothing.) What’s more, even though they’re essentially invisible above ground at least half the year, they must still be cared for according to their cultural needs below ground. In other words, geophytes combine the evanescence of an annual with the maintenance requirements of a perennial. In practical terms, this means that, although temporarily vanished, they continue to take up valuable garden real estate that could otherwise be used for plants that you can, you know, actually see. It also means having to keep the surrounding soil as dry as possible throughout the summer, which admittedly limits what you can plant in their vicinity.

All of these challenges notwithstanding, I am here to tell you that not one of them is insurmountable or reason enough to miss out on the sheer joy to be had from gardening with California’s geophytes. What I’ve learned over the years is that the rumored difficulty of gardening with these plants is not commensurate with the reality, largely based, as it is, on the well-deserved reputations of a few genuinely finicky species. In support of this argument, I’ve put together the following handy-dandy set of FAQs based on my own experience growing geophytes in my garden over the years. If you’re one of those native gardeners out there who’s been reluctant to give geophytes a try, I hope it will encourage you to include these truly magical plants in your own wild landscape.

When is the best time of year to plant native geophytes?

While they may enter dormancy over the summer, native geophytes are best planted out in late fall to early winter, once the weather has cooled and the days are shortening. I’ve found that planting soon after the first rains of the season is ideal. If you do choose to plant them out before the rainy season has begun (i.e., when conditions are extremely dry), be prepared to keep the surrounding soil moist until you observe shoots starting to emerge.

Where should geophytes be sited?

Pick a spot in your garden that receives little-to-no supplemental water during the dry season. If they get too much water in the summer, native geophytes may rot from the unnatural combination of elevated soil temperatures and regular moisture. If you don’t have such a spot, establishing one will be an important part of successfully introducing geophytes to your garden.

It’s also important to consider your geophytes’ surroundings. These diminutive plants can easily get lost or overwhelmed by proximity to larger perennials and shrubs. An exception to this rule may be Mariposa Lilies (Calochortus sp.), which can often be found on canyon slopes, poking up through thickets of chaparral stalwarts like California Buckwheat (Eriogonum species), Mountain Mahogany (Cercocarpes species) and Black Sage (Salvia species).

What about exposure?

With the exception of Fairy Lanterns (Calochortus albus) and Spotted Humboldt Lily (Lilium humboldtii ssp ocellatum), which prefer dappled shade, most native geophytes like full to part sun. Blue Dips (Dipterostemon capitatus), probably the easiest of all native corms, thrives in full sun, but will also bloom reliably in partly shady woodland gardens. (In the wild, they can often be seen blooming under oaks.)

What other native plants work well with geophytes?

Natural companion plants for the meadowy set of bulbs and corms would be grasses, smaller-scale herbaceous perennials like Blue Eyed Grass (Sisyrinchium bellum), other geophyte species and annuals. Geophytes found in Coastal Sage Scrub or Chaparral will do well interplanted among small to mid-size summer-dry species like Wooly Bluecurls (Trichostema lanatum), White Sage (Salvia apiana), California Aster (Corethrogyne filaginifolia), Coastal Prickly Pear (Opuntia littoralis) and Chaparral Yucca (Hesperoyucca whipplei). While most of these plants also experience summer dormancy to varying degrees, they will provide your bulb zone with at least some visual structure during that part of the year when geophytes’ energies have retreated to their storage organs underground.

What type of soil is best?

Native geophytes prefer fairly porous soil, so pick a spot in your garden with excellent drainage. Obviously, woodland species will benefit from more loamy soils with a bit organic matter, while those found in coastal sage scrub or chaparral prefer leaner, sandy or granitic soils. The bottom line is that most geophytes won’t tolerate sitting in soggy soil for long. Planting on a gentle slope (where they are often to be found in the wild) will be appreciated for the same reason.

How should geophytes be planted?

Step 1: Dig a planting hole a little wider than the circumference of the bulb. There are various (and conflicting) views on the proper depth of the planting hole out there, but most often, it’s described as being about three times the length of the bulb or corm. A planting hole that is a little too deep is said to be better than one that’s too shallow, but I’ve found that, in the final analysis, it isn’t all that critical. Do make sure that the bottom of the planting hole has a nice layer of loose fill to improve drainage and encourage deep rooting.

Step 2: Fill the hole with water and let it completely drain a few times if the soil is dry.

Step 3: Place the bulb or corm with its fatter side down (where the roots emerge). As you fill the planting hole, lightly compact the soil around the geophyte.

Step 4: Water the bulb in after planting. It may help to create a little soil berm around the hole when planting on slopes to make sure the water percolates into the soil directly surrounding the bulb rather than just running off.

Keep the soil uniformly moist until you see the first sprouts peeking above the soil line. This can be anywhere from days to months, depending on the time of year, weather and individual species. Water occasionally after that if winter rains don’t materialize.

Pro Tip: Mark the spot where your geophytes are planted with something that won’t deteriorate so that you don’t try planting something in the same spot while they’re dormant and accidentally dig them up. I use landscaping fabric staples for this purpose.

What about predators?

You may want to protect your geophyte from small mammals who like to dig them up and eat them (or just dig them up for the fun of it, which is somehow even more annoying). You can try cutting out a 3” square of small-gauge chicken or other wire and place it over the planting hole, staking the square into the ground with landscaping staples. You can also purchase bulb cages if squirrels, raccoons or other critters pose a threat. (In my experience, mammalian predators are one of the most frequent causes of geophyte failure, preceded only by regular summer watering.) Snails and slugs also like to snack on geophytes and should be controlled.

How should geophytes be cared for during summer dormancy?

After flowering, allow the soil surrounding the bulb to dry out as seeds set and the flower stalk and leaves wither. You can either leave the bulb alone and in place over the summer, or you can dig it up during dormancy if you’d like to move it somewhere else later in the year. If you’re going to cut down the spent stalks, be sure to wait until they’ve fully senesced. The energy of the plant is returned to the bulb (or other storage organ) as it withers and you don’t want to interrupt the process before it’s complete. After that, don’t water at all for the rest of the summer.

Like any other summer-dormant California native intolerant of water when soils are warm, geophytes’ first-year survival in the garden is a roll of the dice. The plant will either make it through its first summer or it won’t. The point is, watering likely won’t improve its chances and can actually be harmful.

If you do dig a bulb or corm up, keep it in a cool, dark, dry place, safe from rodents (an indoor closet is fine) until the fall. Be sure not to store it in an airtight plastic bag or container which could encourage mold – a regular paper envelope will do. I store my dormant bulbs and corms buried in open plastic containers filled with vermiculite to keep them cool, dark and dry. Corms like Blue Dips eventually produce offsets, which can be dug up while dormant and replanted elsewhere in the garden.

When it’s time to plant the geophyte out again in the fall or winter, you can either replant it in the ground or in a small-ish nursery pot until it sprouts and develops this season’s root system before planting.

Where the Bulbs Are: Geophyte Resources

As noted, one of the most difficult aspects of gardening with native geophytes is the fact that there are so few sources available. These are the best I’ve found.

Theodore Payne Foundation
TPF is by far the best local source for California native bulbs and corms. The biggest selection is usually available at their big fall plant sale in October when native bulbs/corms are dormant. Late winter into spring, they usually have some geophytes already started in 4” pots, which takes the guesswork out of planting depth. For the last few years, they’ve had 1-gallon Spotted Humboldt Lilies in early spring, which, given the time and effort that go into their propagation, go for $60 a pop.

Telos Rare Bulbs
The best online source for native bulbs and corms, but as usual with geophytes, it’s all in the timing. Bulbs aren’t shipped until they’re dormant, usually in July, but ordering starts the previous year, with the entire catalog closing for orders on December 31. Telos is a small operation and their entire inventory sells out very quickly, so monitor the site for dates, set your alarm and prepare to be first in line.

Department of Shameless Self-Promotion: LA Native Plant Source began offering dormant Blue Dip corms in 2023. We hope to start adding Common Goldenstar corms to our geophyte offerings in the not-so-distant future. We regularly propagate Soap Plant (Chlorogalum pomeridianum) as well as Scarlet Larkspur (Delphinium cardinale). Every so often, we have a few Spotted Humboldt Lillies for sale. Several generations of local Calochortus species are also currently in production, sale date unknown. Stay tuned!

– Eric Ameria

© 2024 by LA Native Plant Source