Yellow Camellias

John Wang describes his hybridization efforts towards developing yellow flowering camellias.

Yellow Camellias - My Golden Dream

by John Wang

The second California Gold Rush occurred in 1982 when members of the Northern California Camellia Society had a chance to see a small bush of C. chrysantha from the University of California at Berkeley Botanical Gardens. The new camellia species would produce golden yellow flowers.

Only a few members who were working on camellia hybridization had the privilege to obtain a grafted plant. It was so precious that Dr. David Hagmann expressed, “ I wish just to have a few grains of that pollen". Even today, the gold rush fever is still on for many camellia gardeners in many countries.

It was around 1989 that I collected my three C. Chrysantha plants, one from Nuccio’s Nurseries and two from the garden of Jack Osegueda. In my small shady green house, they grew fast and produced the first flowers in 1992. The pollen was immediately introduced on 'Bertha Harms', 'Moonlight Bay', and on C. Octopetala. Many jelly seeds were produced. I kept trying for three years hoping that there might be a miracle to forge a solid seed --- it was never realized. It was a treat that Mr. Julius and Tom took me to their seedling staging area where I first saw the yellow flower on “Shoko” developed by Mr. Datao Yamaguchi. They also showed me some of the yellow camellia flowers on their seedling plants.

BRIDGE PLANT

Every keen camellia breeder seems to have a special instinct to figure out the next step. Matching pollination with C. nitidissima, naturally followed hunting for genetic white flowers in species such as C. japonica, C. reticulata, C. pitardii, C. yhsienensis, etc. If I did not have an opportunity to discover a “mutant, wild form, white C. reticulata in the remote mountains of China, maybe another option would be to develop a new hybrid of C. reticulata in my backyard. All the tools I had were three plants:

'White Reti', developed by Mr. Fish Hamilton of Santa Cruz, Ca. It does not set seed.
'Loretta Feathers', a reti hybrid originated by Mr. David Feathers. He once mentioned that the white color element was likely in Loretta Feathers.
'Suzanne Withers', confirmed by Dr. Bob Withers - plant has parentage of C. reticulata and C saluenensis

The flower color from these three plants is all light but not pure white. Tinge Pink and blush white can be found on the petal. Eventually at least 15 seedlings were produced by these three parent plants. Five seedlings have been blooming for one to three years. The color ranges from “blush white” to “off white”. Luckily the flowers are rather large and all are very fertile. I call this group of seedlings WW (Wang’s White). I consider WW group seedlings my bridge plant. They may help me realize the following:

Because the seed bearing plant (WW) is C. reti hybrid, not C. japonica, normal solid seeds can be produced by WW1 X C. nitidissima. About fifty new seedlings have been produced without extra efforts. Because WW1 is so fertile many seeds can be harvested from one seed pot. I call the seedlings of this type of crossing “ F1 (P) “ seedlings, indicating that the seedling has C. nitidissima as the pollen parent. Now my thought goes back to “Jelly Seed”. The first camellia hybridization task on C. nitidissima was carried out in China in the 1960's and 70's. They discovered that C. reti plant could set normal solid seeds with the pollen of C. nitidissima. If the seed setting plant was C. japonica of similar cross, only jelly seed would be formed. The genetic substance in the cells of my WW seedling plants likely contains 75% to 50% C. reti.

The jelly seed has, I learned, normal embryo development but failure of cotyledon formation. It may be caused by an unknown factor in this regard, not necessarily the percentage of the genetic substance. If the subject is beyond me, I just develop a hypothesis: There is a X factor existing in the fertilized ovary produced by C. japonica X C. nitidissima which may prevent development of cotyledon in the seed.

I might first try to develop some reti hybrid seedling containing 25% or lower reti parentage. If it is possible, then we shall have more work to do to see how low is low to maintain normal seed development.

• Possibly, one of fifteen seedlings can be selected as a show flower.

• To cross it with creamy flower of C. japonica such as 'Brushfield’s Yellow' or 'Ken Hallstone' M32 to produce new white reti hybrid seedlings, hopefully a light color flower with a creamy center. A few seedlings are about two-year old.

• Wishful thinking: to produce a two-tone color flower of reti hybrids, or a white reti hybrid flower with deeper pink vein formation.

• A few reti hybrid seedlings have been produced with the goal of a nice classic camellia show flower mainly in white, light or blush coloration.

F1 (S) & F1 (P) SEEDLINGS
On one hand I was developing the white reti hybrids as bridge plant. On the other, I applied the pollen of “White Reti” on the stigma of C. nitidissima in 1994 to 1995. Three seedlings were successfully produced. In order to speed up my timetable, the seedlings were close-grafted in April of the same year. So far they have been flowering for two to three years. I call these group seedlings “ F1 (S)” because C. nitidissima was the parent seed setter. My evaluation of these flowers:

The flower size was larger than I thought, measured around 3 inches in diameter. Some gibed flowers would reach 5 inches in diameter.
The forms are single and semi double.
The color is very pale creamy to ivory white, the flower center has noticeably deeper cream color. Some flowers have tinge pink cast at the back of the outer petals. The cream shade increases slightly after the flower is in full bloom.
They do not set seed for me yet. The amount of pollen from the seedling flower, F1 (S) varies among seedlings. Some of the pollen might be fertile.

I made crosses of 'Suzanne Withers' and C. nitidissima, during two different seasons. Over fifteen seedlings F1 (P) were produced and three seedlings have been blooming for two to three years. The flower quality is very similar to that of “ F1 (S)” but there is a possible difference - Some F1 (P) seedlings may be a moderate seed setter. So far, both flowers of F1 (S) and F1 (P) all are very rewarding. But we need to go to the next step to acquire more yellow coloration. I should mention Mr. Hulyn Smith's 20 seedlings of identical pollination. He finally kept only four of his seedling plants.

BACK CROSS 1(S)
Like a real life TV show, I have been constantly monitoring the methods, resources and ideas of my hybridization. With F1 seedlings in hand, the next move was logically toward “back crossing”. A total of six back crossing seedlings have been developed. I call them, “BC1 (S)” seedlings. The seed setter was C. nitidissima and the pollen was from “F1 (P)”. The “BC1” can be considered as 75% of genes from C. nitidissima, even though we understand that the yellow pigment of C. nitidissima is not necessarily proportionally transferred to the next generation. Three of my two-year old seedlings have been close-grafted and they grow into 2 & 1/2 to 4 foot tall plants. I hope it will flower in two years. It is too early to tell the outcome of those three BC seedlings. However they have been observed as follows:

The first seedling has an almost identical leaf appearance as that of C. nitidissima. It is likely not a true back cross seedling. Don Bergamini mentioned to me that, “you really don’t know”.
The second seedling has trimmer leaves and more leaf serration. The color is slightly lighter in green color than that of C. nitidissima. The new growth is reddish purple in color. It is possibly a BC seedling.
The third seedling has a high possibility of being a BC seedling. The leaves are as large as C. nitidissima. The leaf has a deep ribbed formation and deeper serration. In my proper shaded green house, C. nitidissima will produce dark forest green leaves under proper care. However, under the identical conditions, the leaf color of this seedling is more closely resembles that of a regular reti hybrid. The new growth stem and leaves are still deep purplish in color.

Right now there are a few BC seed pots growing on the branches of my C. nitidissima plant. If I manage to harvest a few more new BC seeds early next year, I feel it is worthy of all my efforts.

Mr. Yoshikawa and Mr. Yamaguchi of Japan made headlines in the ACS Yearbook of 2000 in the development of impressive yellow camellia flowers. Mr. Gene Phillips is also one of the front runners in this area. A very fine soft yellow flower, 75% genes from C. nitidissima, has been blooming in Savannah, Georgia. More yellow flowers are coming from his garden. I believe that many able gardeners are working hard on the same objective and their new yellow flowers will be here before our eyes. If a camellia gardener has a flower bearing plant of C. nitidissima, one can jump start to develop new creamy or yellow camellia immediately by back crossing. The flower pollen, from F1 hybrids such as 'Golden Glow', 'Honeymoon', etc. is readily available in every area's camellia society. Besides, a dozen of new creamy blend or yellow camellias developed in Japan are offered for sale in Nuccio’s Nurseries. Some of them might have fertile pollen.

When I work on camellia hybridization, particularly with tricky C nitidissima I do observe nature. It takes patience, proper timing and innovation to improve the chance of pollination. I am still at the beginning stage of back crossing. As time goes on, and with frequent practice, many more BC seedlings shall be produced.

BACK CROSS 1 (P)
In the previous year, I tried to use the pollen of C. nitidissima and deposit it on the stigma of a F1 (P) seedling plant. Two seeds were set and later dropped in the summer. It was an encouraging sign for “back crossing on F1 (P) plant”. If BC seedlings are developed by this type of pollination, I would call the seedling group “BC1 (P)”. I have three interesting observations this year as follows:

Six flowers on a F1 (P) seedling plant were introduced with the pollen of C. nitidissima last season. Only one healthy seed pot was set. It has a lobbed shape, looking very healthy on the branch, measured at 1and 1/4 inch in diameter, observed in August of 2002. I have yet to see whether it will be a solid seed.
Unintentionally I found a small seed pot of “open pollination” growing on a branch of another F1 (P) plant in May, so far so good in August. I will try to set seed on the flowers of all F1 (P) seedling plants with C. nitidissima pollen for the next season.
The fertility of this F1 (P) is still under evaluation. It might be more fertile than we have calculated. ( Big “IF” the seed is viable) At the time being, I have limited seedlings and flowers derived from C. nitidissima. The results are still sketchy. But it has been a fascinating ride.

YELLOW FLOWER FROM C. JAPONICA

Many gardeners, including myself, do admire the beauty of the cream flower of C. japonica. Some regard that the cream color is not true yellow. We all know that Mr. Ken Hallstone devoted all his efforts to develop fragrant camellias. Actually, he was also working on a few of the yellow color camellias. His seedlings in this area include:

M32, a small irregular anemone japonica, a Kikoshi and Bontan Yuki origin. It sets seed. The yellow color on petals and on petaloids is very unique, like a spreading wet watercolor painting.
M41, a small to medium anemone flower. The outer petals are white and center petaloids are in vivid cream color. The shape is neat. I plan to register this flower and to name it “Hallstone’s Yellow”.
M46, a small japonica flower, single to semi double with some cream at the center.
A no tag seedling. Small anemone flower in pink merging centrally to form a beautiful cream colored center; the petals are thick with substance. But often one or two petals show uneven folding. It is still held for further evaluation.

My selected seedling in this area is very limited. In 2001-02 season, one of my seedlings from M32 has flowered. A single small flower was off white to pale cream color, a seed setter. It set two healthy seeds with the pollen from F1 (P). The pollen is also fertile. It results in seed pots set on my C. octopetala plant. My second seedling of creamy C japonica origin first bloomed in March 2002. The flower is small, 14 to16 petals in blush white with obvious creamy color under tone.

A few seedlings have been produced by crossing between a white color reti hybrid and a creamy C. japonica intended to develop a reti hybrid flower with cream color in the center. I will likely do more of this type of pollination.

Of course, the best flower in this category is Dahlohnega developed by Dr. Homeyer. A pale creamy, single flower seedling and the light creamy color of “Witman Yellow” were the plant parents to achieve the 'Dahlohega' plant with canary yellow flower. Mr. Conrad Hooper of Florida confirmed the cross. Conrad is a very enthusiastic camellia friend and he had close acquaintance with Dr. Homeyer for years.

YELLOW FLOWER FROM OTHER CAMELLIA SPECIES
“Colored Icons of Yellow Camellias” published by Guangsi Science & Technology Publishing House, Guangsi, China, lists 21 kinds of yellow camellias. Most the flowers are smaller but some of them are very attractive and unique such as C. pingguoensis, C. ptilosperma and C. terminalis. Their potential in yellow camellia hybridization is so far untapped. I have a plant called C. tunghinensis. I did not bother with the plant for years because of the small size of the yellow flower. I made a few incidental crosses last season due to its early bloom characteristics. Five mini sized seed pots are growing on the plant. The pollen plants are C. gigantocarpa, C. granthamiana and C. octopetala. I am waiting to see whether it will be a solid seed in the pot.

I renew my interest in work with C. octopetala. The flower color is indeed creamy. It has very attractive large leaves. The species plant is rather fertile. The seed pod is unique like a Lee-Chi fruit. We need to produce hybrids from different gene pools. It should be beneficial if we have more resources to work with.

The new valuable yellow camellia flowers are coming from northern Vietnam. C. flava is described as a medium, semi double yellow flower. It seems a perfect candidate for hybridization.

SUMMARY

I have to make a comment on the result of my hybridization with C. nitidissima. It does not have enough data to draw any statistical meaning. Nevertheless, it serves as an incidental reference for camellia hybridization.
Development of new yellow camellia flowers is only at its early stage. Any camellia breeder can jump on the bandwagon. The chance to develop new hybrids of “golden” camellia flowers is very favorable.
We shall experience some limitation due to sterile or less fertile flowers in new seedlings. The knowledge developed by the research from many institutions might help us overcome some future difficulties.
In order to further hybridization, I always pay attention to the compatibility of pollination among hybrids of yellow camellia seedlings.
This article shares some of my limited personal experience and knowledge in yellow camellia hybridization from last eight years. I have only a handful of results associated with C. nitidissima. However, the fun and enjoyment I have had in pursuing the "Golden Dream" is immeasurable.