|Romneya subsp. var.||Matilija poppy, tree poppy|
They are perennial subshrub with a woody stem. They may grow to a height of 2.5 meters (8 ft) and a width of 1 m (35 in), with the flowers up to 13 cm (5 in) across. The silvery green leaves are deeply cut, with a small fringe of hairs at the margin.
They are notable for their large white flowers with intense yellow centers, blooming in summer. These flowers prefer a warm, sunny spot and fertile soil with good water drainage. They are not easily grown, and also difficult to remove.
|Standard Cyclopedia of Horticulture|
Romneya (named for T. Romney Robinson, who discovered it about 1845). Papaveraceae. Tall showy herbs or subshrubs used for garden planting.
Stems branching: lvs. petioled, pinnatifid, 2 or 3 pairs of segms. : fls. solitary at the ends of the corymbose branches, large, white and showy, 6 in. across; sepals 3, with a broad membranaceous dorsal wing; petals 6, all alike; stamens very numerous; stigmas numerous, connate at base into a little ring: caps. 7-11-celled, dehiscing to the middle, the valves separating by their margins from the firm persistent placentae.—Two species, Calif, and Mex. Monographed by Fedde in Engler's Pflanzenreich, hft. 40 (IV. 104), 1909.
Romneya coulteri grows wild in California from San Diego to Santa Barbara County and also in Mexico. In the wild, it blooms chiefly in June and July, but in cultivation the period of bloom is increased from May to August. In the Los Angeles basin, it thrives best on dry rocky soil and needs only the water it obtains from the winter rains. Romneya coulteri can be transplanted safely if cut to the ground before it is lifted and can be raised from seed if the seed is fresh. Raising from seed under artificial conditions is not very satisfactory, however, as it takes a few years between the germination of the seed and blooming of the seedlings.
Romneya coulteri is difficult to transplant, due to the scarcity of fibrous roots; in middle California suckers which are produced in great abundance are transplanted without any loss, provided a good firm ball of earth is kept around the stout thick roots in transit, and if the stems are cut well back, almost to the base. At San Francisco it grows luxuriantly in a heavy adobe soil, producing immense flowers. The name Matilija poppy (pronounced Ma-tilli-ha) is the favorite in California. It comes from the Matilija Canon, Ventura County, where the plant grows in particular abundance. Miss Parsons writes: "Many people have the mistaken idea that it grows only in that region. It is not common by any means; but it is found in scattered localities from Santa Barbara southward into Mexico. It is very abundant near Riverside, and also upon the southern boundary and below in Lower California, where the plants cover large areas. It not only grows in fertile valleys, but seeks the seclusion of remote canons, and nothing more magnificent could be imagined than a steep canon-side covered with the great bushy plants, thickly covered with enormous white flowers." Blossoms remain open for many days. (J. Burtt Davy.)
In Southern California, R. coulteri grows best in sandy, well-drained soils. It dislikes summer water and for that reason does poorly near lawns. Home gardeners that are not willing to forego summer watering should avoid this plant. However, if it does not get summer water and is left to grow in a well-drained soil, it can become quite happy, almost invasive as it spreads by underground runners. If not overwatered, R. coulteri an survive in even heavy soil, but will not be as effusive. For a plant that can be exuberant as the Matillija Poppy, this is not necessarily a bad thing.
The plant is easily propagated by cuttings of runners if taken when the plant is dormant or nearly so. A length of root containing several nodes can be placed an inch or so below the surface in a pot of well-drained planting medium and the plant will readily send up shoots. If the pot is at least a gallon, once well-rooted, it can be set out into the garden. Once it is established in the garden it will spread.
By seed, the plant is not as forgiving. The seed sprouts readily if it is fresh and if a fire treatment is used. In a clay pot, scatter the seed, cover with dry pine needles and dried leaves from other trees (because R. coulteri grows often near or with California endemic oaks, using dried oak leaves seems to work better than random leaves). These are set on fire and allowed to burn down, the seeds are watered in and germination takes place within three weeks - no special treatment is used after that, the pot with the seeds is placed in a warm sunny location.
However, once the seed has sprouted, the seedlings at some point must be transplanted into their own container and the mortality of this process is far too high to be anything more than an exercise to teach propagation. Out of 45 sprouted seeds in a recent trial, only 3 survived to actually be planted out in the garden. Propagation by root cuttings is definitely a more successful adventure.
The genus includes only two species:
- Coulter's Matilija poppy (Romneya coulteri) Harvey
- Bristly Matilija poppy (Romneya trichocalyx) Eastwood - some consider this a variant Romneya coulteri var. trichocalyx