Sidalcea

( sye - DAL - see - uh )

At-A-Glance Information

This genus of flowering perennials and annuals includes species which need full sun and regular water to perform well in the garden. They are grown for their beautiful, wide-petaled flowers that bloom in mid to late summer in shades of white, pink, and purple. Species are commonly called Checkerblooms, Checkermallows, False Mallows or Prairie Mallows. Most species are native to western and central North America. Use these flowers in mixed beds and borders in cottage, informal, pollinator, or wildflower gardens.

Sidalcea Species and Varietals

The Sidalcea genus includes approximately 25 species of flowering plants, and is a member of the plant family Malvaceae. Checkerbloom grows best in zones 2-10 and 14-24, though this can vary somewhat depending on the species. For more information, see the descriptions below. To find your zone, click here: Zone Map.

Sidalcea calycosa (Annual Checkerbloom, Checker Mallow, Vernal Pool Checkerbloom)
This species is endemic to California, where it grows along the northern coastline and adjacent mountain ranges south towards the San Francisco Bay Area. These plants prefer wetland habitats, and reach between 1 and 3 feet tall when in bloom. Green leaves are narrowly divided, and flowers are pink, purple, or white, blooming from April through September.

Sidalcea candida (White Checkerbloom, Pairie Mallow, White Checkermallow, Wild Hollyhock)
This High Plains native reaches 2-3 feet tall and 1.5 feet wide, spreading by rhizomes. Leaves are bluish-green and flowers are white, forming in spikes in mid- to late summertime (typically between June and September).

Sidalcea Hybrids
Members of this group of Checkerbloom are grown commonly in gardens, and are hybrids between Sidalcea candida and Sidalcea malviflora. They reach about 2 feet wide and can bloom all summer if deadheaded. Choice selections include 'Brilliant' (with carmine flowers), 'Party Girl' (reaches 2-3 feet tall with deep pink flowers), 'Elsie Heugh', 'Oberon', William Smith' and 'Rosanna' (also 2-3 feet tall, with rose-colored flowers).

Sidalcea malviflora (Checkerbloom, Greek Mallow, Pairie Mallow, Dwarf Checkermallow)
This species grows best in zones 2-9 and 14-24 and is native to Oregon, California, and Baja California. Reaches 2 feet tall and just as wide, and has a sprawling habit. Early springtime flowers are purple-pink and attract butterflies. This species needs moderate water for best performance. Cultivar 'Loveliness' produces shell-pink flowers.

Sidalcea neomexicana (Salt Spring Checkerbloom, Rocky Mountain Checker-Mallow, New Mexico Checker)
Best in zones 2, 3, 10-13 and 18-24, this species is native from eastern Oregon through Wyoming and south through Mexico. It grows to 3 feet high and about half as wide, with spikes of white to pinkish-white flowers that bloom in summertime.

Caring for Sidalcea

Plant your Sidalcea in full sun to partial shade; ideally they like to get around 6 hours of sun each day, with some shade in the afternoon when temperatures are at their peak (typically between 2 and 3 PM). Ensure that soil is well-draining, moderately fertile, and has a pH of between 6.0 and 7.0 (slightly acidic to neutral). 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 as they establish a strong root system in their new home. At maturity, Checkerbloom appreciates regular waterings. As a general rule of thumb, water whenever the top inch or two of soil feels dry to the touch.

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. These plants are not heavy feeders, and this should be sufficient to provide the necessary nutrients for the active growing and flowering seasons. Deadhead spent flower spikes when blooms fade to encourage more to form. This will also discourage self seeding, though if you plant on harvesting seeds later on for propagation, you will want to leave some spent flowers on the plant. Sidalcea plants form clumps over time which will need to be divided every few years (or more often if they are grown in a cramped space or container). For instructions on how to successfully divide Checkerbloom plants, see the Propagation section below.

Propagation

Sidalcea, or Checkerbloom, can be propagated by division or seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the division 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, especially if you are propagating a hybrid cultivar. To propagate your Checkerbloom, follow the instructions below:

Propagating Sidalcea 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. 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. You will also, after a few weeks, need individual 3-inch pots for each seedling that grows.
Harvest your seeds. The seed heads on plants are pretty easy to spot, they're left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will continue to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Get your container prepared. 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 2-6 weeks 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 65 and 72 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.

Propagating Sidalcea by Division
This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil (any kind will do, though it does need to be well-draining), compost and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in very early spring (after the plant has entered dormancy, but before it has begun its new spring growth), and needs to be done every few years regardless of whether you have the goal of propagating the plants for best performance. To propagate by division, follow these steps:

Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the root(s). Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots with your gloved fingers. Once the roots are untangled, separate your plant into segments, ensuring that each one has at least one thick root section attached.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divisions and water thoroughly.
Apply a thick layer of mulch over the new planting to protect it from cold weather as it acclimates to its new home. Then, enjoy watching it sprout in the next growing season.