CAMELLIA SOIL MIXES FOR LANDSCAPE AND CONTAINERS
By Brad King --
Camellias prefer a well-drained soil that is high in humus and slightly acid. A pH of 7 or less is acceptable but 5.5 to 6.5 are ideal. The use of coarse peat moss or oak leaf mold provides humus and the acid condition. When either is mixed in equal parts with "sharp" or "potting" sand a loose well-drained quality mix is obtained. Fine peat moss frequently found in garden centers is not recommended. It easily becomes too wet or too dry; both conditions lead to loss of camellias.
LANDSCAPING: When planting a camellia in the ground determine your soil conditions. A simple test is to wet the soil and grasp a handful of soil. If it remains loose and formless it is sandy. If it forms a one or two inch ribbon it is loamy and if it forms a two inch or more firm ribbon it is clay. If your garden soil is sandy add oak leaf mold or coarse peat and small pine bark in equal parts in a hole dug twice the size of the root ball. If the soil is loamy it has acceptable conditions but adding equal parts sand and humus to the soil will provide optimal growing conditions. When the garden soil is clay or adobe remove as much of it as possible. Add in equal parts sand, medium sized pine bark and humus (coarse peat moss or oak leaf mold). This will make the soil well drained, acid and rich in humus. The pine bark decomposes slowly keeping the mix loose for a longer period of time. When it decomposes it does remove some nitrogen. However it is a sound trade off to keep the soil loose and to fertilize with either cotton seed meal or a camellia azalea commercial fertilizer once or twice a year. Do not fertilize the first year you put a camellia in the ground.
Camellia roots need to breathe. Soggy wet soil and dry hard packed soil destroy roots. In other word camellias thrive in moist-not wet or dry conditions. Therefore add ingredients to your garden soil to get the optimal balance for your conditions.
CONTAINERS: Camellias thrive in pots but require special care for them to grow and flower. Camellias in containers require repotting or potting up every two or three years. The soil becomes depleted, soggy and heavy after three years. Potting up is useful when a plant outgrows its container. For example a camellia doing well in a one gallon pot should be potted up to a three gallon pot after two years and so on until the plant reaches the size the grower desires. After that the plant is repotted every two or three years, in the same size container. When repotting roots are trimmed an inch or two with a knife then put back in its container with fresh potting mix. While the same principles as a camellia in the ground are followed, more careful attention is required.
First, the container must have adequate drainage holes because camellias can't tolerate wet feet. The bottom layer of the pot can be gravel, broken crock, coarse wire mesh, etc. I prefer two or three inches of coarse pine bark.
Second is the potting mix. Do not use ordinary garden soil because it gets too hard and its' humus is depleted quickly. The most convient method is to use a ready made commercial camellia azalea mix from your local garden center. However many growers make their own mix. My current mix is equal parts small pine bark, sand, oak leaf mold (or coarse peat moss) and a high quality commercial camellia mix. The commercial mix has "composted fir bark, sphagnum peat moss, mushroom compost, volcanic pumice stone, earthworm castings, bat guano, kelp meal, feather meal, gypsum and a natural wetting agent yucca shidegera sponen. The percentages are not listed for this product. I would assume percentages can change and that various commercial mixes can have different ingredients.
Third, a camellia in a container will require fertilization. The easiest solution is to purchase a commercial camellia azalea fertilizer using it as directed on the label. These products are to be used only during the growing season -- April through September. Never feed a dry plant and be careful not to over feed especially during hot weather (over 90 degrees). A popular alternative is to use cotton seed meal during the growing season. It is organic and much less likely to burn the plant. A successful alternative is to use four parts cotton seed meal to one part iron. This will keep the foliage green and flower colors vibrant especially the reds. Note how much nitrogen is combined with the iron. An N=2 or 3 is optimal and one over 10 can be dangerous as it is combined with the nitrogen in the cotton seed meal for a total exceeding 15.
A fourth method is to use a liquid fertilizer formulated for acid loving plants that can be applied with a watering can or foliage spray during the growing season. The best example is Miracle-Gro for azalea, camellias and rhododendrons. Please note that Miracle-Gro contains a high level of nitrogen -- nitrogen 30; phosphate 10 and potassium 10 and all the iron and trace elements needed for healthy camellias. Therefore, I recommend cutting the manufactures amount in half especially for small plants and non reticulata hybrids. Do not use it when temperatures are above 90 degrees. Since my goal is to produce winning flowers for Camellia show, I use Miracle-Gro for camellias and azaleas every two weeks, four to six times ending in the middle of June. During the rest of the summer growing season I use cotton seed meal every 45 days. During the dormant season from October through February when buds are developing and blooms appear a 2-10-10 fertilizer is applied.
A number of other Southern California Camellia show exhibitors begin the growing season with an application of fish emulsion, followed by four parts cotton seed meal, one part iron and one part blood meal every 45 days during the growing season and 2-10-10 during the dormant season every 45 days.
Camellia seedlings grown in pots require fertilizing once the seed has been absorbed. Cotton seed meal is acceptable but the commercial dry fertilizers may be too strong for "babies". I prefer a liquid starter fertilizer applied every two weeks during the growing season which is cut in half during the dormant season. The objective is to keep the nitrogen level low (N=2 and never above 3) during dormancy. This is the period for bud and flower development in camellias so some phosphate and potash is desirable.
Finally, take time to enjoy your flowers. Blooms may be cut and used to decorate your home. One or a collection of blooms floated in a shallow bowl with water makes an attractive centerpiece. A container plant may be moved to a patio or window to better show its flowers as long as it is outdoors and has shade.