horticulture digest...university of hawaii u.s. department of agriculture cooperating in this issue:...

HORTICULTURE DIGESTDepartment of Horticulture Cooperative Extension ServiceUniversity of Hawaii U.S. Department of Agriculture Cooperating

In this Issue: FLOWER AND NURSERY INFORMATION

No. 6, November 1971

FROM THE EDITOR

This is the fourth in the Horticulture Digestseries on Flowers and Nursery Information. Wehope that it is providing you with interestingand useful information. We would like to thinkthat this is your newsletter and would sincerelywelcome your comments and suggestions onhow we can better serve your needs.

Mahalo,Fred D. RanchAssistant Specialist

in Horticulture

CHEMICAL PRUNING OF AZALEAS

Two azalea cultivars, 'Skylark' and 'Whitewater,' were sprayed with 3 percent and 5 percent concentrations of two chemical pruningagents, Off-Shoot-0 (Proctor and Gamble) andEmgard 2077 (Emery Industries, Inc.). Theplants were grown in 6-inch containers at theManoa glasshouses or in ground beds at theKula Experiment Station at 3,200-foot elevationon Maui.

Plants at Manoa were handpruned May 13,1970 to shape them; the plants at Kula weresheared at the beginning of July to stimulatenew growth. The Manoa plants were sprayed atmidday on May 15, 1970; the Kula plants atmidmorning August 14, 1970. About 4 weeksafter spraying, the number of new laterals were

counted on 7 representative shoots for each ofthe 14 plants in each treatment. The data arepresented in Table 1.

It is obvious that more laterals were stimulatedby handpruning than by the chemical pinch.However, it must be remembered that handpruning was necessary to shape the plant and thatconsiderable labor can be saved in subsequentsteps by using chemical pruning agents to stimulate additional breaks. The 5 percent concentration would be selected as more effective. Thelower concentration could be used on plants protected from rapid drying or at early or late hoursof the day when less active ingredient would belost due to evaporation. In these tests, Emgard2077 was the more effective chemical pruningagent.

A chemical pruning agent should not beapplied too soon after handpruning. If new laterals have been activated by the handpruning, theymay be destroyed by the chemical. Allow 4 to6 weeks for new growth to develop and maturebefore applying the chemical.

There are numerous reports in the literatureof the chemical pruning agents being used onother plant materials. At present, however, theregistration for these materials is limited toazaleas. Growers who wish to try them on otherplant materials will find the following list a guideto plants which have responded to chemicalpruning: (0.5 to 2%): chrysanthemums, agera-

Table 1. Average number of new lateral shoots on Azalea 4 weeks after spraying with Off-Shoot-0 or Emgard 2077.

Treatment

HandprunedNo pruning3% Off-Shoot-0

5% Off-Shoot-0 .3% Emgard 20775% Emgard 2077

'Skylark'Manoa Kula

3.4 —

1.4 0

2.2 2.8

1.7 2.4

2.4 2.6

2.0 • 2.4

'Whitewater'Manoa Kula

3.0 —

1.4 1.7

1.6 2.9

1.5 2.8

1.6 2.9

2.2 3.2

turn, snapdragon and other herbaceous plants;(3 to 5%): cotoneaster, forsythia, carnation,American elm; (6% or higher): cornellia, holly,mockorange, some conifers, some fruit trees—guava. In chrysanthemums, carnations and poin-settias there are differences among cultivars inresponsiveness to the chemical pruning agents.

Richard A. CrileyAssistant Horticulturist

EXTENSION STAFF CHANGES

Oahu CountyGeorge Santos, Jr. is a new extension staff

member, appointed to work in the KaneoheOffice effective April 1 as an Assistant in Extension. This is a new position, created to provide help in conducting applied research projectsand to assist with telephone and office calls fromthe public.

George earned his B.S. degree in agriculturefrom the University of Hawaii. Before taking theextension job he worked for the Phillip MinnNursery as a horticultural aide. While still inschool, he worked during the summer as a ranch-hand for AmFac. He was a member of the AggieClub at the University.

Hawaii CountyTadashi Higaki has been appointed County

Extension Chairman, Hawaii County, effectiveJuly 1, 1971. He replaces Bob Ota, who hasa new role as Assistant Dean, College of TropicalAgriculture. Mr. Ota will coordinate the teaching,research and extension activities of the Collegein Hawaii County. Warren lkcda will assumeresponsibility for extension activities for orchids,and Yoshio Watanabe will carry on the extensionwork for all other flowers and ornamentals including turf.

SCHOLARSHIP AWARDED

The California State Florist Association'sBoard of Trustees of the Joseph Shinoda Memorial Scholarship Foundation recently announcedthat Miss Linda Kiyomi Mochizuki has beenawarded a S500 scholarship for the academicyear 1971-1972. Miss Mochizuki, from Kaneohe,will be a senior this fall at the University ofHawaii, majoring in horticulture in the Collegeof Tropical Agriculture. Miss Mochizuki wasselected from a large group of highly qualifiedapplicants for this award. The $500 award isgranted for high scholastic achievement and continued study in the field of floriculture.

NURSERY NOTES

Home Purchase

In a recent survey conducted by United StatesHome and Development Corporation, it ,was

found that automatic lawn irrigation was thesecond most wanted extra when purchasing ahome. The first was central air conditioning.

Selling Plants JMany nurseries continue to buy and sell plants "^

in rusty cans simply because they are cheaper.However, it has been established that a plant inan attractive container will outsell the same plantin the proverbial rusty can every time. Anotherproven method of selling plants is to featurethose that are in bloom. It is to our advantage tomerchandise our products as attractively aspossible.

Highway Planting PolicyA new planting policy has been designed to

improve highway beauty in Connecticut. Aspecial provision of the policy is that contractorsbe required to be responsible for a plant establishment period of one year, the period to startafter all plant materials called for in a specificcontract have been planted.

if. S. Imports of Horticultural ProductsA recent report by the USDA shows that U.S.

imports of horticultural products reached anall-time high in 1969. The value of fresh and processed vegetable imports, the leading commoditygroup, increased nearly fivefold over the 1956value. In contrast, nursery stock imports'showedthe least growth of all the commodity groups.These were valued at $16 million in 1969, 26percent above the value imported in 1956. About80 percent of the nursery imports originated inthe Netherlands-most of them were bulbs, withtulip alone accounting for 38 percent of thetotal.

Competition from Discount StoresMany florist and nursery operators have be

come concerned about the increased sale of plantmaterial through discount stores. Service is thechief weapon used by St. Andrews GardenCenter and Nursery Company in combattingcompetition from department stores which haveopened during the past couple of years in thesuburban area of Columbia, S. C. The GardenCenter has competitive prices in most areas butthe department stores do undersell on someitems. The Garden Center's answer is service and

quality merchandise.

Combat Pollution

One acre of growing forest produces about 4tons of oxygen a year—enough for 18 people ayear.

GOOD RESULTS

FROM SOFTWOOD CUTTINGS

Softwood cuttings generally root easier andquicker than the other types of cuttings but

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