Crown daisy is a native of the Mediterranean that has widely naturalized in Asia, where it is a popular leaf vegetable. In seed catalogs, you might find it listed under Asian greens, its Japanese name, shingiku, or its Chinese name, tong hao. The plant has also naturalized in parts of North America to the point of becoming invasive in some areas such as southern California, where it chokes out native species such as native daisies. Crown daisy can invade disturbed areas, wasteland, and coastal dunes. If you are planning to grow crown daisy for its edible leaves, spring and fall is the best season, especially in warmer climates because summer heat intensifies the bitter taste of the leaves. You should thin small plants to 4 to 6 inches apart, and taller plants to 10 to 12 inches apart. The leaves can be harvested when young and tender or fully mature.
Light
Crown daisy can be grown in full sun or part shade. If you grow it primarily for the leaves, shade is fine. To promote flowering, plant it in a sunny location.
Soil
The plant adapts well to any type of soil, as long as it is well-drained, moist, damp but not wet, and rich in nutrients and organic matter.
Water
Young seedlings need constantly moist soil. Water regularly in the absence of rain. Once the plants are well-established, crown daisy only needs watering during dry spells.
Temperature and Humidity
As a native of southern Europe, crown daisy is not frost tender. The optimal growing temperature is between 68 and 84 degrees F. In hot summer weather, crown daisy might flower prematurely.
Fertilizer
If the soil was fertile and rich in organic matter to start with, there is no need for fertilization.
Types of Crown Daisy
There are two types of crown daisy, broadleaf and narrowleaf. The leaves of the broadleaf types are also thicker which makes them more tolerant to hot summer weather. The narrow leaves are thinner and often frilly; the plants have a brighter green color than the broadleaf varieties.
Propagating Crown Daisy
Crown daisy can be propagated from seed. Before collecting seeds, make sure what you have grown in your garden is an open-pollinated variety and not a hybrid, so that the plants will be true to their parents. Collect the seeds from the spent flowers. The seeds are very small, similar to lettuce seeds.
How to Grow Crown Daisy From Seed
In the early spring, in a well-prepared garden bed, sow the seeds in a row, ¼ inch deep and 2 inches apart, leaving 18 inches between rows. Thin the seedlings as they grow, and keep them moist at all times. If you are living in a warmer climate with a late first frost date, you can also plant a second crop in the fall. Check the days to maturity on the seed package. For baby leaves, it takes about 30 days to maturity, and for full-size greens, 45 days. Count back from your average first frost in the fall and time your planting so that you get to harvest the greens before the first fall frost.
Common Pests & Plant Diseases
Crown daisy is not affected by any major pests and diseases.
