Sternbergia

( stern - BER - jee - uh )

At-A-Glance Information

This genus of flowering herbaceous perennial plants includes species that grow from bulb and need full sun and regular water during their growing and blooming periods. They are commonly called Fall Daffodil, Lily-of-the-Field, Winter Daffodil, and Yellow Autumn Crocus. These flowers are native to Eurasia and northern Africa, and have golden-yellow to white flowers that bloom in early fall. Leaves typically remain on the plant through wintertime and fade away in the following spring, though flowering and leafout timing varies depending on the species grown. They are great choices for planting along pathways or the edges of patios. Take care when planting these flowers in the garden, as plant parts (especially underground rhizomes) are poisonous if consumed by humans or pets.

Sternbergia species and vArietals

The genus Sternbergia includes just 8 species, and is a member of the plant family Amaryllidaceae. The genus is named for Austrian botanist Count Kaspar von Sternberg. Sternbergia grows well in zones 3-10 and 14-24. To find your zone, click here: Zone Map.

Sternbergia candida
These rare plants are native to southwestern Turkey, where they grow on the edges of Cedar woods. They produce green to grey-green leaves that appear in late wintertime, with white flowers that follow in January to February in the plant's native range. Flowering stems reach about 8 inches tall and are topped with white flowers with protruding stamens.

Sternbergia clusiana
These bulbous flowering plants are sometimes grown as ornamentals, and produce golden yellow flowers in fall. They are native to Turkey, Iraq, Iran, Lebanon, Syria, Israel, Palestine, and the Aegean Islands. Leaves are grey-green and appear after flowers have bloomed in winter to early springtime in the plant's native range. These are not recommended for areas that have winter frost; they perform better under the protection of a greenhouse in these climates.

Sternbergia lutea (Winter Daffodil, Autumn Daffodil, Fall Daffodil, Lily-of-the-Field, Yellow Autumn Crocus)
This species is native to the western Mediterranean region through central Asia, and dies back to the ground in summertime. These ornamentals produce deep yellow blooms that appear soon after glossy green leaves emerge. Individual plants reach up to 4-5 inches tall and 1.5 inches wide when mature and in bloom.

Caring for sternbergia

Sternbergia plants are typically purchased as bulbs, planted out in the garden in a space that receives full sun to partial shade. They love to be under deciduous trees and shrubs, and can naturalize in the garden over time. Plant bulbs 4 inches deep and 6 inches apart for best coverage. 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, Sternbergia flowers require regular waterings during their active growing and blooming season, but prefer soil to stay on the dry side during their dormancy in summertime.

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. Prune to remove spent flower stems (unless you will be collecting seeds for propagation). Leave all foliage on the plant until it has yellowed and then died back to the ground; until leaves are fully browned, they can still photosynthesize and store nutrients for the following growing season. If your winter temperature drops below 20 degrees Fahrenheit, make sure to cover the bulbs with a layer of mulch to protect them over the winter months. Divide Sternbergia clumps only when they are struggling to perform as normal (typically every 4 years); they otherwise do not do well if disturbed. For instructions on how to successfully divide Sternbergia plants, see the Propagation section below.

Growing Sternbergia in Containers
Sternbergia, or Autumn Crocus, can be grown either in the ground or in containers. Around 5 bulbs can fit into a 6" pot. This is a great option if your area gets snow during the winter or if the ground freezes; pots can simply be brought into a sheltered area over the cooler months of the year. Ensure that soil is well-draining; rocky substrate is commonly used in container situations. Water regularly during the active growing and blooming period, and withhold waterings during dormancy in summertime. Adding a layer of mulch to the top of the pot can go a long way in suppressing weed growth, maintaining consistent soil temperatures, and increasing soil moisture retention. Prune to remove spent flowering stems (unless you will be collecting seeds for propagation). Sternbergia blooms better when it is a bit pot-bound, but if plants start to struggle or not bloom well, it is an indicator that they should be divided. For instructions on how to successfully divide Sternbergia plants, see the Propagation section below.

Propagation

Sternbergia, or Autumn Crocus, 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 Autumn Crocuses, follow the instructions below:

Propagating Sternbergia 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.
Physostegia seeds will need a period of cold-stratification in order to germinate. To complete this process, first place seeds in a bag or other sealable container filled with moistened sand or peat moss. Then, place the container in the refrigerator (or similarly cool, dark space) for 2-3 months. The ideal temperature for cold-stratification is around 40 degrees Fahrenheit. After this period has passed, remove seeds from the container.
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 Sternbergia 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.

Problems and Pests

Sternbergia, or Autumn Crocus, plants are typically considered resilient, though they can be susceptible to developing issues with the following pests and diseases in the landscape from time to time: