M„ 
 
 A Publication of The College of Agriculture 
 
 UNIVERSITY Of CALIFORNIA 
 
 w ' 
 
 A WARM 
 ER CLIMATE 
 
 5UY JYL M. WINSLOW 
 
 CALIFORNIA AGRICULTURAL 
 EXPERIMENT STATION 
 
 CIRCULAR 406 
 
PEACH VARIETIES 
 
 F 
 
 JLor 
 
 or a number of years, plant breeders have 
 been working to develop peach varieties with 
 a low enough winter chilling requirement to 
 produce well in southern California, and thus 
 help to restore what was once a major fruit 
 industry in that area. They have had some 
 success. 
 
 While the main reason for the shrinkage in 
 peach acreage in southern California since the 
 early 1930's was economic, a secondary but 
 highly important reason was that most of 
 the better-known peach varieties needed more 
 winter chilling than is provided by the normal 
 climate in that area. 
 
 The varieties described here were developed 
 at the University of California's Agricultural 
 Experiment Station. All are relatively new; all 
 have moderate or low chilling requirements 
 and should produce well in southern Califor- 
 nia. Their faults, as well as their good points 
 (based on their behavior at Riverside) are 
 listed. 
 
 THE AUTHORS: 
 
 J. W. Lesley is Geneticist in the Experiment Station, Riverside. 
 M. M. Winslow is Senior Administrative Assistant, Riverside. 
 
FOR A WARM WINTER CLIMATE 
 
 J. W. LESLEY • M. M. WINSLOW 
 
 About 25 years ago, peaches were an 
 important crop in southern California, 
 with over 27,000 acres being planted to 
 this fruit. 
 
 During the ensuing period, however, 
 economic conditions such as low prices, 
 and poor varieties which suffered from 
 a condition known as delayed foliation 
 influenced many farmers to turn to other 
 crops. 
 
 Thus the 1950 report of the California 
 Crop and Livestock Service showed that 
 in that year peaches in southern Califor- 
 nia accounted for only a little over 5,600 
 acres, bearing and nonbearing. 
 
 However, in a few localities in south- 
 ern California (notably the Ontario and 
 Yucaipa districts in San Bernardino 
 County, and the Beaumont and Banning 
 Heights districts of Riverside County) 
 table peaches are still important in the 
 local market. And it is felt that the re- 
 cent large increase in population of the 
 metropolitan areas of southern California 
 should provide an expanding market for 
 locally grown fresh peaches. 
 
 Development of 
 New Varieties 
 
 As early as 1907 it was found that 
 many varieties of peaches then being 
 grown were not well adapted to the lower 
 elevations of southern California where 
 a subtropical climate prevails. It was ob- 
 served that most of these varieties were 
 subject to prolonged dormancy, due 
 mainly to lack of chilling during the rela- 
 tively warm winters which are character- 
 istic of the region. 
 
 Therefore plant breeders initiated a 
 program to attempt to develop new varie- 
 ties that would require a relatively short 
 period of winter chilling — that were bet- 
 
 ter adapted to the warmer areas of south- 
 ern California. 
 
 The first successful variety was the 
 Babcock peach. Subsequently, further 
 work along this line was undertaken at 
 the University of California Citrus Ex- 
 periment Station, at Riverside, and the 
 varieties described in this circular were 
 all developed at that Station. The descrip- 
 tions of the varieties given below are 
 based on their behavior at Riverside. 
 
 Effect of Winter 
 Chilling on Peaches 
 
 The amount of chilling weather en- 
 countered during any given winter will 
 affect the time of both blooming and 
 often of fruit ripening of peach trees. The 
 flower buds of peaches normally open 
 after they have received enough winter 
 chilling followed by weather that is warm 
 enough to induce their opening. Thus a 
 warm spell early in February will cause 
 the flower buds of a very short-chilling 
 variety to open, but not those of a long- 
 chilling variety — the latter has probably 
 not received sufficient winter chilling at 
 that early date and may not bloom until 
 a month or more later. After an unusually 
 cold winter and spring, long- and short- 
 chilling varieties differ much less in date 
 of blooming. 
 
 After a mild winter, the ripening date 
 of short-chilling varieites in some years 
 is advanced by as much as 2 or 3 weeks, 
 whereas the ripening date of long-chilling 
 varieties is little affected. 
 
 Short-chilling varieties have their 
 drawbacks too. If, after an unusually 
 warm winter, a late frost occurs, very 
 short-chilling varieties may lose their 
 crops if freezing temperatures come dur- 
 ing or after bloom. Therefore, varieties 
 
 [3] 
 
Bonita tree, 5 years from budding. 
 
 that require less chilling than those in 
 grade 3 may be undesirable for the inter- 
 mediate zones of southern California. In 
 the coastal belt there is much less danger 
 from spring frost, and at high elevations 
 the colder spring weather tends to delay 
 blooming sufficiently to escape frosts. 
 
 The varieties described here are 
 graded from 1 to 7 on their requirements 
 for chilling. Grade 1 signifies the shortest 
 chilling requirement; grade 7 the long- 
 est. The grades given are based on the 
 behavior of the varieties at Riverside. 
 
 All of these varieties are freestones, 
 with the exception of Ramona, which is a 
 cling. All are self-fertile — will produce 
 fruit from their own pollen. 
 
 All, with the exception of Anza, were 
 developed for the areas in southern Cali- 
 fornia having warm winters (graded 4 
 or less for chilling requirement) . All but 
 Prenda, Golden State, and Ramona can 
 be obtained from several California nurs- 
 erymen. 
 
 Here Are the 
 New Varieties 
 
 Anza 
 
 The tree is rather upright and only 
 moderately vigorous. This attractive, yel- 
 low-fleshed freestone is firm, sweet, and 
 juicy. The flesh is of good texture and 
 
 
 
 Fruit of the Bonita variety. 
 
 quality. Anza has possibilities in the 
 areas mentioned for the Rubidoux (see 
 below), but is not recommended for low 
 elevation areas in southern California. 
 Anza falls in grade 5 for winter chilling 
 and requires less, by one grade, than the 
 J. H. Hale. This variety begins to ripen 
 the second week in August. 
 
 Bonita 
 
 The Bonita is a vigorous, upright type 
 of tree. The foliage is dark green. The 
 leaves hold on late in the fall. It is an 
 excellent producer. The fruit is medium 
 to large in size. The skin color is a light 
 yellow with a deep red blush. It is an 
 attractive fruit. The flesh is yellow with 
 a dark pink seed cavity, and with fingers 
 of pink extending into the flesh. The flesh 
 contains some fiber. The flavor is sweet 
 with a touch of bitterness in some sea- 
 sons. The quality is good. It is a promis- 
 ing peach for the home garden and for 
 small commercial plantings near the 
 coast. Bonita falls in grade 2 and requires 
 less winter chilling than Babcock. It ma- 
 tures late in July. 
 
 Golden State 
 
 The tree is a vigorous, upright grower 
 at Riverside. The fruit is large and firm. 
 The skin is a lemon-yellow color with a 
 
 [4] 
 
Hermosa tree, 5 years from budding. 
 
 marbled red blush on one side; not at- 
 tractive in appearance. 
 
 The flesh is light yellow with a light 
 pink seed cavity and rather coarse. The 
 flavor is fair and slightly subacid. This 
 variety is an irregular producer, subject 
 to preharvest drop, and therefore not 
 promising. Golden State falls in grade 3 
 for winter chilling. The first fruits ripen 
 the first week in August. 
 
 Fruit of the Hermosa variety. 
 
 Hermosa 
 
 The tree of the Hermosa is of fair vigor 
 with a rather spreading type of growth 
 similar to the J. H. Hale. It has large, 
 conspicuous flowers. It is a heavy bearer, 
 coming into production early. The fruit 
 is medium in size. The skin color ranges 
 from pink to solid red. The flesh is white, 
 with a pink seed cavity. The flavor is 
 sweet and mild. Hermosa falls in grade 
 
 Fruit of the Prenda variety. 
 
 [5] 
 
Fruit of the Ventura variety. 
 
 3 for winter chilling. The fruit begins 
 ripening the middle of August. The va- 
 riety has sold well at roadside stands. 
 It is recommended for the home gardener 
 who likes a sweet, nonacid-tasting fruit. 
 
 Ramona 
 
 This cling peach is borne on a vigor- 
 ous, upright tree. The fruit is of a good- 
 size, yellow fleshed, and produces an 
 excellent canned product. It tends to pro- 
 duce many twin fruits thus lessening its 
 commercial value. It is later than the 
 Fontana, another cling with a short chill- 
 ing requirement. Ramona falls in grade 3 
 for winter chilling. This cling is the last 
 of the varieties to ripen, being ready for 
 harvest about the second week in Sep- 
 tember. 
 
 Prenda 
 
 The Prenda is a vigorous, upright- 
 growing tree, and a good producer. The 
 leaves are a dark green. The fruit is me- 
 dium to large in size. The smooth skin is 
 a light cream color with a red blush on 
 one side, near the stem end. The flesh is 
 
 white, smooth in texture, and juicy. The 
 flavor is mild, sweet, and pleasing. Like 
 most white peaches, the aroma is attrac- 
 tive. It has not been grown outside of 
 the Riverside area and is not yet avail- 
 able from nurserymen. It is also subject 
 to preharvest drop of the fruit. Prenda 
 falls in grade 2 for winter chilling. It 
 ripens with Golden State. 
 
 Rubidoux 
 
 The tree is vigorous, and moderately 
 spreading. It retains its leaves into late 
 fall. Good production can be expected. 
 The fruit is medium in size. The skin is 
 greenish-yellow with a dull red blush. 
 It is one of the best keepers of those de- 
 scribed. The flesh is light yellow and the 
 deep red of the seed cavity extends into 
 the surrounding flesh. The flesh contains 
 some fiber. This sweet, well-flavored 
 peach has promise for the higher eleva- 
 tions in southern California. It merits a 
 trial in the upper San Joaquin Valley. 
 Rubidoux falls between grades 3 and 4 
 for winter chilling. The fruit starts to 
 ripen the last of August. 
 
 [6] 
 
Sunglow 
 
 The tree is a vigorous, upright grower. 
 The foliage is dark green. This variety 
 produces well. The fruit is medium-large 
 in size. The skin color is golden yellow 
 with a red blush. The flesh is light yellow 
 with a medium-pink seed cavity. The tex- 
 ture is smooth. This juicy, rich-flavored 
 fruit should be popular with consumers. 
 It certainly has a place in the home gar- 
 den. It is somewhat subject to preharvest 
 drop. Sunglow falls in grade 4 for winter 
 chilling. It starts to ripen the first week 
 in August. 
 
 Ventura 
 
 This variety first produced fruit in 
 1942 as seedling 202-10. It is the earliest 
 
 to ripen of the varieties listed, maturing 
 early in July. The tree is 'vigorous and 
 upright. For winter chilling it is in grade 
 2. It was named after Ventura County 
 on the southern coastal plain where it is 
 reported by C. C. Delphey, Agriculturist 
 in the Agricultural Extension Service, to 
 show some promise. 
 
 The fruit is slightly flattened at the 
 poles, almost without a pointed tip; at- 
 tractive in appearance, but rather small 
 in size. The skin is yellow with a red 
 blush. The flesh is yellow, contains very 
 little red color, and is free from the pit. 
 The fruit often shows a twig mark due 
 to the short pedicel or stem. The flavor 
 is subacid and the quality fairly good. 
 
 LITERATURE CITED 
 
 The following articles and publications were used as source material in the preparation of this 
 circular: 
 
 Chandler, W. H., M. H. Kimball, G. L. Philp, W. P. Tufts, and Geo. P. Weldon. 
 
 1937. Chilling requirements for opening of buds on deciduous orchard trees and some other 
 plants in California. California Agr. Exp. Sta. Bui. 611. 
 
 Chandler, W. H., and Dillon S. Brown. 
 
 1951. Decidous Orchards in California winters. Calif. Agr. Ext. Cir. 179. 
 
 Lammerts, W. E. 
 
 1941. An evaluation of peach and nectarine varieties in terms of winter chilling requirements 
 and breednig possibilities. Proc. Amer. Hort. Sci. 39:205-211. 
 
 Lesley, J. W. 
 
 1939. Five new peach varieties especially adapted to mild winters. Univ. of Calif. Agr. Exp. Sta. 
 Bui. 632. 
 
 10m-4,'53(A3034)W.P. 
 
 Second Printing 
 
 [7] 
 
test tube farming 
 pays off for you 
 
 Not all of the agricultural research done by the 
 University of California is field work. Much useful 
 knowledge comes to light through work done under 
 controlled laboratory conditions. 
 This information, after thorough checking and 
 application to field problems, becomes available to all 
 California farmers. Distribution of this knowledge 
 is made through: 
 
 LITERATURE: 
 
 Circulars, bulletins, lithoprints, and leaflets by specialists are 
 available free. There publications cover many subjects re- 
 lating to agriculture in the state. For a catalog of this litera- 
 ture write to the Office of Agricultural Publications, 22 
 Giannini Hall, University of California, Berkeley 4. 
 
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 Farm Advisors are agricultural specialists with a background 
 of practical knowledge. They serve 52 counties throughout 
 the state and their mission is to help farmers work out their 
 problems. Get to know your Farm Advisor — take advantage 
 of his services. 
 
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 problem will be referred to the person or department best ^ 
 able to give you the exact information you need. 
 
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 UNIVERSITY OF CALIFORNIA