By Richard Flowers, ACCNP-Green Thumb Nursery-Ventura
There is a specialty plant group that is often over looked and doesn’t get the attention it deserves. These plants belong to the family called Proteaceae. Plants included in this family are Grevilleas, Protea Leucospermum, and Leucodendron. Read on for more information on these plants. This grouping of plants encompasses some of the most fascinating, interesting, and durable plants around. They are humming bird magnets and attract butterflies too. Protean plants range from ground covers, shrubs, trees and even a fruit tree ( the Macadamia). Their floral displays range from pincushions (Leucospermum), cones (Leucodendron), to spidery or tubular structures(Grevillea). Most of these plants thrive on almost neglect, low water, low maintenance, and in fact if you have too good of a soil or fertilize in some cases they will not thrive. Welcome to the Proteaceae family.
These plants are native to South Africa and Australian and are fire adapted chaparral plants in their native habitat so you can think of them as our version of chaparral you see in the hills. These Southern Hemisphere plants love our mediterranean climate because these drier regions of the world are much like the climate of Southern California.
They are forgiving, tough, and underrated plants however to be successful growing them, they prefer all day sun, exceptionally well draining soil that is acidic with little summer water once established in open ground and are able to take much less drought stress than most plants. Do not over water! For optimum success plant on slopes or mound the soil so they are growing above grade so they could achieve good water penetration, air flow, and water movement throughout the soil. The #1 thing that kills them is over water. Once established during the summer they need occasional watering. Never apply water at the crown, instead irrigate where all the branches and leaves come out. Until they become established water every 3 to 4 weeks deeply and slowly. In coldest coastal areas no summer water.
These plants can grow in coastal or cool inland areas but keep them away form freezing temperatures. Although they are moderate frost hardy, damage can occur at 25 degrees F. Younger plants are more tender to frost. Best to provide shelter form hot, drying winds. If growing in containers make sure the container is partially shaded and keep roots cool. Although the plant is somewhat drought-tolerant, it benefits from regular water during warm, dry weather. Water early in the morning so the plant has all day to dry before the arrival of cooler temperatures in the evening, helping to prevent leaf and stem fungi from forming.
The species have evolved and adapted to thrive in warm, dry climates with relatively low to moderate rainfall and temperatures moderate to very warm. The majority of these plants are adapted to poor soils that drain very well. Many of the Proteaceae have specialized proteoid roots . Proteoid roots are masses of lateral roots and hairs forming a radial absorptive surface, produced in the leaf litter layer during seasonal growth, and usually shriveling at the end of the growing season. These roots are an adaptation to growing in poor, phosphorus-deficient soils and greatly increasing the plants access to scarce water and nutrients by exuding carboxylates that mobilize previously unavailable phosphorus. Their succulent, proteoid roots make them very forgiving as container plants, tolerating erratic or inadequate watering very well. These roots are amazing in that since, however it is not advisable to disturb these delicate roots when gardening or planting them. When planting, I recommend to remove the container it is planted in from the root ball and gently placing the plant in the planting hole taking care not to touch the roots.
When growing these types of plants in your landscape successfully, they need little or no fertilizing in California soils. If used, fertilizer should lacking in phosphate, the middle number on a fertilizer container. Never apply phosphorus, it can be detrimental at even ‘normal’ soil levels to Protea or others related. Phosphate toxicity shows up initially as yellowing foliage, progresses to blackened leaves, and can eventually kill the plant. Almost all will benefit from iron applications. When fertilizing, never over fertilize
and feed with foliar spray of iron chelate or use soil sulphur. Likewise you can also use cottonseed meal. In most cases sulfur or other pH-dropping agents, placed a couple of feet away from the new plant will provide a permanent fix by offering the roots a hyper-acidified zone within which iron is always available.
When planting them in your garden use cactus mix which provides sharp drainage, the more drainage the better. They also need plenty of room, and good air circulation, meaning that the plants should not touch
one another or be crowded next to other things.
Using these plants in the landscape offers many advantages. Many if not all do well in containers. Several selections may be used as screens, focal points, specimen plantings, and flower and foliage décor. Many varieties can be utilized as a hedge or formal plantings. A few types could be as a ground cover or an accent plant.
One of the best features of these plants is their extended blooming periods. All are highly attracted to hummingbirds, which feed gluttonously on the nectar. Below are the main plant groups in the Protea Family.
Grevilleas are mostly native to Australia and are a diverse group of plants they could be ground covers, evergreen shrubs to stately trees. These plants are commonly called Spider Flower because their flowers are loved for their intricate and spidery bloom, some even have a pleasing, sweet fragrance. Grevilleas are subtropical and tropical shrubs and trees that sport a variety of types of foliage. Species with needlelike foliage are especially useful for adding interest to a planting of palms or other tropical plants with big leaves. Broad-leaf Grevilleas are a welcome addition to any planting area. Use the larger-growing tree types to cast shade or act as a windbreak. Shrubby types can be used as hedges and privacy screens or planted to provide an extra dose of color and texture in the back of garden beds and borders. Compact types grow well in large containers, so you can enjoy these varieties on your deck or patio, even if you don’t have a yard to plant them in. And because most types like hot weather, they’re good choices for containers on driveways and other paved spots. Grevillea foliage color ranges from yellow-green to medium and dark green. Bloom colors include white, pink, yellow, and orange.
Leucodendrons are commonly called Cone-bushes because the seed heads which are woody cone-like structures gave rise to their common name- Cone bush. Their flowers are actually quit small but the showy part you see are actually bracts which are modified leaves that occur mostly in the winter. They are native to South Africa and are quite valuable for their mostly attractive, durable, often rich green or reddish tinged summer foliage and neat, almost formal habits. The flowers are produced in dense
inflorescences at the branch tips. Leucos(short for Leucodendron) are dioecious, with male and female flowers on separate plants. All can be used for cut “flowers,” have attractive, decorative cones, and some are used for their cut green foliage as well. Cone-bushes make very forgiving and underrated container plants. Some are used for silvery or silky foliage effects and willowy or wispy habits.
The Leucospermum ( Pincushion) genus consists of approximately 50 species, most native to South Africa where its natural habitat includes mountain slopes, scrubland, and forests. Depending on the variety, Leucospermum ranges from low-growing groundcovers to small trees. Some varieties have become popular indoor plants, valued for the colorful, pincushion-like blooms. They have long, slender tubular flowers on a thistle like head. The leaves are narrow on stalks and crowded on the stems. Most are
grown for the floral trade.
I feel it is imperative to not leave the crowing jewel of what the Proteaceae family is named after-The Protea. Despite being the most seldom seen for sale as plants, an article about Protacea family plants would not be complete without something to say about them. Linnaeus named the genus Protea after the Greek god Proteus, who, according to legend, was able to transform his shape and appearance into numerous animate and inanimate forms at will and it was from this name that the family name
Proteaceae was assigned by the French botanist Jussieu. Proteas have tubular flowers in tight clusters surrounded by brightly colored bracts and most are only grown for the floral trade. They are native to South Africa and are amongst the oldest flowering plants on the planet, with fossils dating back 300 million years.They are also called “sugar bushes” due to their production of copious amounts of nectar. The Protea is commonly associated and symbolizes diversity, transformation, longevity, and courage.
Green Thumb caries a range of these rugged and unusual plants that will fit very well into a drought tolerant Mediterranean garden. Try incorporating them with cactus and succulents which will be an excellent match together. We have an extensive selection of other Mediterranean and drought tolerant plants that will work very well with Protean plants or any garden you decide to create. Please call ahead for specific availability, availability changes regularly.
Do you like what you see? Sign up for our weekly newsletter to get content like this every week!