APRIL 1950 H. M. BUTTERFIELD FORNIA AGRICULTURAL EXTENSIO ICE • THE COLLEGE OF AGRICULTUR VERSITY OF CALIFORNIA • BERKELE * v It / * A well-filled plant of Debutante, pruned to espalier form to enhance its decorative effect. Given the right kind of attention, camellias will reward the grower with a wealth of exotic, delicate beauty that is matched by very few flowers grown in home gardens. \jamelh ameiitas require somewhat more attention than most garden ornamentals, and success in raising them is not always certain. However, the delicacy and beauty of camellia blooms is a delightful reward for the trouble undertaken. Csriei) need: Soil that is slightly acid. Shelter from too much sun and wind. Adequate irrigation. Fertilizing— but each plant's needs must be judged individually. Cfl: so: They are reasonably free from attack by pests and diseases. They may be propa- gated by cuttings, by grafting, or may be raised from seed (if the grower has enough patience) . The blossoms should not be cut, but if the temptation is too great, take as little of the stem as possible. This circular gives rather complete cultural directions for the successful growing of camellias. On the back pages are tables of the more popular varieties of camellias, together with comments on their growth and habits. The Author: H. M. Butterfield is an Agriculturist in the Agricultural Extension Division, Berkeley. Cover photo; A pleasing arrangement of Mrs. Charles Cobb. The blooms are much better than usual for this dark red variety. 3] Kjamellla Ljulture in C^aLifc There is a tremendous amount of satisfac- tion to be had from the production of beautiful camellia blossoms. Perhaps this accounts for the huge growth of popu- larity in camellia culture both as a hobby and as an industry in California, since the introduction of the plant in the 1850's. Camellia fanciers have formed a num- ber of organizations which serve the pur- pose of standardizing varietal names, working out growing problems and mak- ing cultural information available to any- one interested, from the professional grower to the newest amateur. Among these are the American Camellia Society (a national organization), and (in Cali- ornia fornia ) the Camellia Society of Kern County, Northern California Camellia Society, Pomona Valley Camellia Society, San Diego Camellia Society, Santa Clara Valley Camellia Society and the Southern California Camellia Society. Camellia plants are, in many respects, like people. They must be treated as indi- viduals. They are subject to a certain amount of "temperament," so that it is difficult to set up any hard and fast rules that will govern their behavior patterns. This fact should be kept in mind when applying the information contained in this circular to individual, local condi- tions. There are 10 or more distinct species of camellias, but of these, only 3 are con- sidered to be of importance at the present time. These 3, Camellia japonica, C. reticulata and C. sasanqua, will be the only ones dealt with at any length in this circular. The most popular varieties grown in California at present belong to the species C. japonica, a native of Japan and China. The flowers may be pink, red, white or variegated in color. The leaves are about 4 inches long, glossy green, ovate or ellip- tic, with sharp serrations. The photos on pages 6-7 show the latest classification of the varieties of C. japonica into 8 classes. These plants will tolerate temperatures down to about 10° F. C. sasanqua is also a native of China and Japan, but is more straggling in growth and not as hardy as C. japonica. It is primarily of interest because it flowers early. It comes in 2 colors, white and pink. Flowers range from single to semidouble and occasionally double. The Japanese varieties are most popular in California branches are pubescent young and the midribs of the (hairy) when leaves are inclined to be hairy also. The leaves are glossy green and about 2 inches long. They are similar in shape to those of C. japonica. C. reticulata is a native of China. Plants are usually sparsely foliated and are not as compact as many Japanese varieties. The plant commonly sold in California as C. reticulata is only one of perhaps 20 or more varieties of this species. It has rose pink flowers that average from 5 to 7 inches in diameter. The petals are wavy (see photo, page 5) which adds to the popularity of the flower. The leaves are about 5 inches long and the same shape as those of C. japonica. Other species of camellias may become popular in the future, but at present they are of interest only to collectors and plant breeders. Classification as to Form of Flower The botanical characteristics of camel- 4] lia flowers are used to segregate the many varieties into 8 classes that are widely accepted by growers. This classification is based largely on work done by Dr. H. Harold Hume and Mr. R. J. Wilmot of the University of Florida. These classifications are given in the chart on pages 6-7. Naming Varieties The most commonly accepted names for camellia varieties are those originally given to them, or those made official by the American Camellia Society. Where the original names have been lost, new names have been given, in some cases. In other cases, new names have been substituted for Japanese names that were difficult to remember or to pro- nounce. In the tables starting on page 19 a fairly complete list of varieties, with synonyms, is given for the more popular varieties. In all cases, the only names con- sidered valid in this circular are those officially recognized by or adopted through legislation of the American Camellia So- ciety. Most people like to start growing ca- mellias by purchasing well-developed plants because the older plants are usually more resistant to unfavorable conditions and will produce more flowers. Cost, how- ever, may be a limiting factor. If time is of less importance than cost, camellias may be grown from seed, from cuttings, or by grafting. These methods are slow and somewhat hazardous, and are described fully under "Propagation." Location may be another factor. While camellias may be grown successfully in nearly all parts of California, the best blooms seem to be produced in places where the summers are warm and the winters are chilly. Growers in the interior valleys seem to have the highest percent- age of prize blooms, since climatic con- ditions there are more favorable than they are along the cooler coastal regions. However, when growing camellias in the valley regions, it is usually necessary to provide some overhead shelter to pro- tect against the extreme summer sunlight. Selection of Plants Avoid buying plants which appear to be stunted, or which have roots that are badly matted in the pot or container. Such plants may never be healthy. Ljetibucj started with camellias is expensive Signs of good health in camellia plants are as follows: 1. Healthy dark green leaves. 2. Good flushes of growth each year. 3. Absence of dead wood. 4. A compact plant for the variety con- cerned. If the plant can be tipped out of the container, examine the roots to be sure that they are not badly matted. The blooms of Camellia reticulata are rose pink, with wavy petals, and average from 5 to 7 inches in diameter. Here is a good specimen. UameLUi l Name of Class: Single. Petals: Has 5 to 7 and sometimes 9. Stamens: All central, united into a cylinder. Name of Class: Semidouble. Petals: Has more than 9, and usually from 14 to 20. Stamens: All central, united into a cylinder. Name of Class: Incomplete Double with Large Petals. Petals: Has numerous large petals. Stamens: Single stamens, or bunches of stamens or both intermixed. Name of Class: Incomplete Double with Small Inner Petals. Petals: Numerous small petals within the guard petals. Stamens: Single stamens or bunches of sta- mens or both intermixed, forming an irreg- ular mass. KjlassLjLcatioYi Name of Class: Incomplete Double with Large and Small Inner Petals. Petals: Numerous large and small petals within the guard petals. Stamens: Single stamens or bunches of sta- mens or both, forming an irregular mass. Name of Class: Double Irregular. Petals: Irregularly arranged in a convex mass, usually small, straplike, and folded, with an outer row of normal petals. Stamens: If present, are few in number and hidden by petals. Name of Class: Double, Incomplete Imbricated. Petals: Imbricated except for relatively large, unopened center. Stamens: None visible. 8 Name of Class: Double, Regular Imbricated or Tiered. Petals: Regularly imbricated (overlapping like a shingle), or tiered (laid one on top of the other). Stamens: None. The Planting Site Most camellias need protection from too much hot sunlight, and from drying winds. A north or east exposure will usually provide sufficient shade. In the central valleys it is sometimes well to provide overhead protection against too much sunlight during the middle of the day, but since camellias need a good amount of heat during the summer season, the overhead protection should not be such that it denies the plants the heat they need. Latticework is prob- ably the best method of providing the correct amount of protection. This is not so important in the cooler coastal regions. Wind may injure the tender new leaves and cause the blooms to deteriorate rapidly. Any kind of injurious gas or chemical in the air about the plants will have the same effect. Some of the corky cell growth on the underside of the leaves may be due in part to wind damage. A plant site should be chosen that will provide shelter against the prevailing winds in the region, or some permanent windbreak should be built. Rain or heavy dew may affect the opened blossoms, but about the only way to protect against wet weather is to pro- vide plants with a temporary roof of some sort. Potted or tubbed plants may be taken to a sheltered porch ; a tarpaulin may be put over the latticework; speci- men blooms may be covered with cello- phane. Rain, however, is not a serious problem. Soil Requirements Camellias grow well in a variety of soils, but need a slightly acid condition to do their best. Soil reaction is measured in terms of pH value, which refers to the acid-ion concentration. Neutral soil (neither acid Uamellias won t do well just anywhere nor alkaline) tests pH 7. In California some tap water tests pH 8 or higher and soils often test pH 7.5 or higher, meaning that they are decidedly alkaline. A reaction of pH 5.5 is considered about right for good results with camel- lias. Since soils vary greatly in pH value, and other growth factors are usually far more important, it is impossible to specify any exact interval between applications of acidifiers. One grower applied aluminum sulfate about once each 4 to 6 weeks but that is more often than is required in most cases. It may not be necessary to use acidifiers if acid fertilizers are used regu- larly and the soil is about neutral to start with. Soil testing outfits may be used to de- termine the acidity of the soil where danger is believed to exist. If the soil is too alkaline and the plants are exposed to hot sun the leaves will begin to show signs of yellowing. In this case a good soil acidifier may be required. It takes only a small amount of acidi- fier to change the reaction of any soil. From % to % pound of aluminum sulfate is sufficient in many cases to acidify one square yard of soil about a plant. The kind of water used may have some bearing on the soil reaction. A water that is high in lime may need the addition of acid before being applied to camellias. Here again, only a small amount of acidi- fier is needed. For example, tap water testing pH 9.2 required only one drop of sulfuric acid to 15 gallons of water to bring the reaction down to pH 6. Copious irrigation at proper intervals will help prevent alkali salts from accu- mulating near the surface. The use of acid peat moss or acid leaf mold will usually be adequate to insure proper acidity in soil around camellia plants. [8] Acid type fertilizer further aids in maintaining soil reaction between pH 5.5 and pH 6. Planting or Transplanting Camellias should be transplanted shortly before their new growth pushes out in late winter or early spring. Digging the plants while they are in active growth is not desirable. Transplanting much later than the time that new growth starts may seriously retard the plant. Plants should not be left in contain- ers longer than one year if this can be avoided. If it becomes necessary to hold larger plants in tubs, they should be re- potted often enough to avoid crowded or matted roots. The time element mentioned above also Watering Camellia plants need watering from the beginning of the dry season in April, up until the start of the rainy season, which may be as late as November. The plants may make 2 or even 3 flushes of growth during this season, and the greater the leaf surface exposed to dry air, the more water the plant will use. A good rule of thumb in watering is to make sure that the water penetrates down to the full depth of the root system. This requires using judgment, and may be difficult to accomplish because of differ- ences in soil condition and in the size of the plants. Here is one method of determining how much water is needed : Set a cup or pan on the ground so that it catches some of the water from a sprinkler. Measure the time it takes to catch one inch of water in the plan. This is the amount of time it takes to deliver one inch of water to the entire soil surface covered by the sprinkler. applies to transplanting into the open garden where the plant is to grow perma- nently. This should be done in late winter or early spring. Make a hole big enough and deep enough so that the roots can be spread out in their natural position. Several inches of good drainage material, such as gravel, small rocks, sand, or broken pieces of flower pots should be spread at the bottom of the hole so that there will be no danger of water collecting around the roots of the plant. The plant should be set so that after the soil has settled it will stand at about the same depth as it did before transplanting. Avoid planting too deep— a practice that may aggravate trouble with brachy- rhinus grubs (see page 17). Cjooa cuituraL practices will help considerably An inch of water applied to the surface of sandy soil should wet down to a depth of about 12 inches. The same inch of water will wet an intermediate loam down to a depth of only 6 to 10 inches, and a fine-grained clay soil down to only 4 or 5 inches. Thus if the camellia plant is in sandy soil, and the roots extend down 24 inches, it would take 2 inches of water delivered to the surface to penetrate down and cover the entire root system. The same plant, in intermediate loam soil, would require about 4 inches of water on the surface; in clay soil, about 5 inches. Frequency of irrigation is also deter- mined by the soil texture. Heavy clay absorbs more water than sandy soil, and the greater the water-holding capacity of the soil, the less frequently it needs to be irrigated. Thus a camellia plant in sandy soil, which does not hold water, might need irrigating every 4 to 10 days; the same plant in intermediate loam would only [9] need watering once every 8 to 15 days; in fine-grained clay every 15 to 30 days. Insufficient watering will usually result in a dull coloring in the leaves, rather than the normal shiny green. The roots can not take up adequate amounts of nourishment unless the soil moisture is above the permanent wilting point. A surface mulch of well-rotted leaf mold, or of acid peat moss, will hold con- siderable moisture and have a cooling effect on the surface roots. It may also prove unfavorable to weed growth. The addition of a 2-inch surface mulch once or twice a year is desirable. Tillage Tillage is not needed for camellias be- cause they are shallow rooted and heavy tillage will harm the surface roots. Weeds that appear may be hoed out, or pulled out, or killed with a weed spray, if pre- cautions are taken to protect the camellia leaves against spray injury. Fertilizers Young camellia plants, with shallow root systems, set out in a fertile soil need little or no fertilizer at the start. After the plants have become estab- lished and have had time to use up most of the available soil nutrients they will respond to small applications of fertilizer given every 4 to 6 weeks. This practice has been shown to be more effective and probably more economical than large ap- plications made only once or twice dur- ing the year. Applications of fertilizer should be started at the end of the rainy season and at the beginning of new growth for the plant. At that time the plants are in the greatest need of nitrogen. This is usually during March or April. Organic fertilizers, such as cottonseed meal, fish meal, blood meal, and manu- factured sludge can provide adequate amounts of nitrogen for the younger or smaller plants. Older or larger plants may need extra commercial fertilizer during the growing season. The amount of fertilizer to use on any given plant is best determined by watch- ing the plant itself. In other words, a thriv- ing plant is the one best indication that it is getting sufficient nutrients. The difficulty in determining any exact amount of fertilizer to apply is due to the differences in the sizes of plants, differ- ences in root systems, and differences in the fertility of soils. The table shown here, however, may be used as a basis for de- Rate of Applying Some Fertilizers No. of ounces* Fertilizer per 100 sq. ft. of soil Sulfate of ammonia 18 Ammonium nitrate 12 Uramon 9 Treble superphosphate 6 Superphosphate 14 17-7-0 23 16-20 ammonium phosphate-sulfate 24 Complete mixed fertilizers (acid type) 1 per cent nitrogen 36 8 per cent nitrogen 50 6 per cent nitrogen 64 Divide by number of applications per year for amount to apply at one time. [10] ciding how much fertilizer of a given type to try out. For very fertile soil or for smaller plants, the amounts shown may be lower; for less fertile soil or larger plants, the amounts may need to be increased. The above fertilizers may be used sepa- rately or in combination to meet the local need. Woody or shrubby plants such as the camellia should not require much addi- tional phosphate fertilizer, since many California soils already have a good supply. When a phosphate fertilizer is needed, then treblephospate might be in- cluded at the rate of about % ounce at each of four applications during the year. One well-known acid-type mixture con- tains the following: pounds acid phosphate 38 cottonseed meal 28 potassium sulfate 17 ammonium sulfate 10 aluminum sulfate (used as acidifier) . . 10 But in making up any acid-type mix- ture as the one above, it should be remem- bered that most California soils are not deficient in potash, and may be only slightly deficient in phosphate, as re- quired by camellias. Therefore the inclu- sion of potassium sulfate may not give any noticeable benefit. Phosphate may be needed only in small amounts, if at all. It may be that the expense of these ingre- dients can be saved by leaving them out of the mixture. Nothing short of actual tests under local conditions will indicate clearly what fertilizing program is needed. Even lab- oratory tests are of little or no value be- cause other, and more important factors such as water, soil fertility, and tempera- ture are closely related in affecting the plant growth. Pruning Camellias require very little pruning. What pruning is done should consist of removing unwanted branches, shortening •in of long branches to give the plant a more desirable shape, and some pinching back of new growth to encourage branch- ing. Pruning should be done toward the end of the dormant season— about March or April. All cuts should be made just above a bud or lateral. Never cut back into old wood where no leaves are present. This will greatly retard, or even prevent fur- ther growth. The natural growing habits of the va- riety should be encouraged. Some vari- eties are spreading; others are upright; some make very slow growth ; some grow rapidly. Some are naturally compact and bushy, but others should be tipped back occasionally to keep them symmetrical. Chandleri Elegans, for example, is a spreading variety and the main stem should be allowed to continue upright growth until it has reached the desired height. The spreading side branches may be pruned back slightly, if desired. A vigorous variety, such as Romany (see photo) may make as many as 3 flushes of growth during the season, with each growth from 4 to 8 inches in length. Certain branches may be removed en- tirely, and others may be shortened in a little. The main upright stem may need support by tying to a stake. Most of the vigorous varieties should have their pruning completed before April 15. When pinching back, to keep the bush compact, one or more buds of the new growth should be left to continue over-all growth of the plant. Some varieties will start to form flower buds on the first flush of growth. This new growth should not be pruned away unless necessary for shaping the plant. Disbudding Disbudding may be done on some va- rieties to improve the size of blooms. The practice will not help much, if any, in preventing bud drop where growing con- 11 This is an example of good pruning— before and after. This vigorous young plant of Romany, or Belgian Red, had made three flushes of growth during the year. Photo at right shows the same plant after pruning and staking. Note much better shape of bush. ditions are not favorable. (See "Bud Drop," page 19.) When camellias form more buds than can be developed properly, the excess should be removed. This should be done as soon as the buds have finally set, and it is possible to determine which are the most promising buds to be left on. Cutting Flowers Strictly speaking, camellia blooms should not be cut at all, if the best inter- ests of the plant are to be considered. This is due to the fact that the buds which are to produce new shoots and enhance the value of the plant are just behind the blooms in the axils of the leaves, and it is difficult to remove the flowers without in- juring or removing the new growth. The next best practice, then, is to re- move as little stem as possible when cut- ing flowers. This may be done best by cutting the flower where it joins the stem. (NEVER BREAK OFF THE FLOWER.) The blossom can then be floated in a shal- low cup or flat bowl, where it will keep fairly well. If it is felt necessary to have flowers with longer stems, to satisfy a certain arrangement, make cuts just above a leaf bud, or back to a healthy lateral. Remove no more leaves than absolutely necessary. Occasionally a leaf will be attached so closely to the base of a flower that it has to be removed in cutting. But this type of cutting should, where possible, be con- fined to those varieties that make long growth during the season, and which have longer stems. Cutting these varieties will present less danger of damaging the fol- lowing year's crop of flowers. [12]