WO1998050322A1

WO1998050322A1 - Method of establishing hops by application of ammoniated zinc metal alkanoates

Info

Publication number: WO1998050322A1
Application number: PCT/US1998/008867
Authority: WO
Inventors: David Shelton
Original assignee: Platte Chemical Company
Priority date: 1997-05-06
Filing date: 1998-05-01
Publication date: 1998-11-12

Abstract

A method applying an aqueous ammoniacal ionic solution of zinc alkanoates fertilizer to hops plants cuttings is disclosed which accelerates the establishment of plants from the cuttings. Particular utility has been found with the application to hops plants. In the preferred embodiment, the solution is applied to a hops plant cutting by pouring the fertilizer solution in a hole which has been dug to receive the cutting. The most preferred aqueous ammoniacal ionic solution of zinc alkanoates includes zinc acetate, and the most preferred hops plants are varieties of dwarf hops.

Description

METHOD OF ESTABLISHING HOPS BY APPLICATION OF AMMONIATED ZINC METAL ALKANOATES

Field of the Invention The present application relates to growing hops More particularly, the present invention relates to a technique for establishing new hops plants from cuttings by application of a fertilizer composition

Background of the Invention

Humulus Cannabaceae is the family of vines which produces the hops used to flavor most beers As can be appreciated, the significant worldwide market for beer means that hops are an important crop in the United States, Great Britain, Canada and elsewhere

A number of species of hops are grown commercially worldwide For example, Humulus lupulus, or common hop, is cultivated widely Humulus lupulus neomexicanus (previously H Ameπcanus), is native to the Rockies and is substantially similar to Humulus lupulus Dwarf varieties of Humulus lupulus, including the variety First Gold available from Wrights of Ipswich, Suffolk, England, and Breeder Rights Horticultural Research International of Wye, Kent, England, are in demand because of their particular aroma, which, like other English Aroma hops, contribute to the high quality and character of traditional English beers

Commercially grown hops are perennial vines grown from roots which are typically planted in rich soil in the spring Vertical support is needed because the vine, depending upon variety, may reach 5 to 25 feet in total length by midsummer Copious amounts of water are preferably provided throughout early growth to support the demands' of the vine Light green hops, which are soft flaky cones of bracts and flowers of 1 -2 inches in length, form in late summer If plants are well established, they will produce hops for harvest in the second year and thereafter In Great Britain, hops are grown commercially in yards or gardens, with the plants three fee apart in rows eight feet apart Shoots emerge from the ground in March or April and are 'trained' or 'tied' by hand onto supporting strings Traditionally, the strings have to be replaced every year, and run from a ground peg at each plant to a supporting wirework lattice, sixteen feet above the ground The hop shoots or bines climb the string quickly to reach the top of the wirework in June Dwarf hops are grown on a wirework trellis half this height The plants then form lateral branches, thicken up in growth and shade the ground between the plants The lateral branches produce flowers which develop into small leafy fruits which are the hop cones required by the brewer The cones swell, increasing in weight, and are usually harvested during the month of September before they become ripe

In England, hops are usually grown in fertile, well-manured soils These soils usually contain sufficient trace elements to supply the needs of the plant However, hops exert a high demand on the soil in the summer months, and the uptake of nutrients in July and August is reportedly rapid It is perhaps not surprising then, that temporary symptoms of various mineral deficiencies can be observed at this time Foliar sprays, for example Maxicrop™ Triple, a 3-0 6-2 5 fertilizer made from seaweed extracts containing 0 005% by weigt zinc in an EDTA complex, and Fertileader Arbo™, a 3-0-0 fertilizer containing 0 3% by weight zinc in an ammo acid complex, have been applied to hops However, experience has shown that such application may not substantially benefited the treated hops unless a serious mineral deficiency is present Indeed, a recent test indicates that application of urea may adversely affect the alpha-acid content of the hops As a result of formal studies and of grower experience, hop growers will generally not use foliar feeds unless the plants are under stress in the summer months Since treatments in the summer months may be too late be beneficial, foliar treatment of hops is not widely used

To obtain the best possible yield from one year old plants planting techniques which will result in the early establishment of healthy hop plants are preferred One technique utilized to promote establishment of Dwarf hop plants involves the misting of root cuttings Indeed, high quality planting of misted cuttings have been shown to return full crop yields in only 15 months

Recent experimentation on dwarf hops has shown that the size of dwarf hop roots grown from misted cuttings could be slightly increased by adding nitrogen to the water applied in the planting hole In particular,

Fertileader Arbo™ fertilizer has been used to so drench dwarf hop cuttings at planting Results obtained were a slight improvement over control cuttings planted at the same time, however, the slight improvement would not expected to be sufficient to compensate for late planting, which occurs when weather at scheduled planting time may be inclement or may have been preceded by a wet winter or spring In such cases, planting may take place later than desired, and late-planted cuttings may not be established sufficiently for the crop to achieve profitability by harvest time in the second year

Thus, while there are innumerable fertilizers available, there is little incentive to use these fertilizers with hops, given (i) the minimal improvement experienced with Fertileader Arbo™, (n) the common perception that application of fertilizers is not expected to be helpful when the soil in which the hops are grown is fertile and well-manured, and (in) summer foliar treatment may be too late It is therefore not surprising, that many fertilizers do not teach application of the fertilizer to hops For example, U S Patent No 4,352,688 for "Nitrogen Fertilizers", U S Patent No 3,909,229 for "Plant Nutrients", U S Patent No 3,997,319 for "Fertilizing Method", and U S Patent No 3,854,923 for "Process for Producing Ammoniacal Solutions of Zinc Alkanoates", collectively incorporated herein by reference, generally describe fertilizers containing ammoniacal ionic solutions of zinc carboxylates, the patents describe tests in which such fertilizers are applied to corn, and nowhere mention hops

It is against this background that the significant improvements and advancements of the present invention have taken place Obiects of the Invention

It is the principal object of the present invention to accelerate the establishment of hops grown from cuttings

It is a further object of the present invention to provide a technique for establishing hops plants grown from cuttings when planting of the cuttings is delayed

It is a yet further object of the present invention to provide a technique in which the time required to plant hops cuttings and to accelerate establishment of the hops plants from the cuttings does not significantly different from the time required by currently used methods Summary of the Invention

In accordance with the major aspects of the present invention, a method of accelerating the growth of hops plants is disclosed in which the plants are fertilized with an aqueous ammoniacal ionic solution of zinc alkanoates In the preferred embodiment, the solution is applied to hops plant cuttings Most preferably, the fertilizer solution is added to holes to receive the hops plant cuttings The most preferred aqueous ammoniacal ionic solution of zinc alkanoates includes zinc acetate, and the most preferred hops plants are varieties of dwarf hops

When using the method of the present invention the establishment of hops plants has been accelerated by a week or more over control plants

Thus, it is contemplated that the method of the present invention may enable growers to profitably establish hops plants from cuttings even when planting of the cuttings is delayed one week or more the method of the present invention does not require excessive labor, multiple applications of a fertilizer, special techniques or special equipment Thus, accelerated establishment of hops plants from cuttings can be economical A more complete appreciation of the present invention and its scope can be obtained from understanding the following detailed description of presently preferred embodiments of the invention, and the appended claims Detailed Description of the Invention

In accordance with the present application, it has been discovered that application of a nitrogen/zinc fertilizer to hops cuttings accelerates the establishment of hops plants grown from the cuttings Particular utility has been found with the application of aqueous ammoniacal ionic solutions of zinc alkanoates to hops plants In the preferred embodiment, a solution is applied to hops plant cuttings Most preferably, the fertilizer solution is added to the holes which receive the hops plant cuttings The most preferred aqueous ammoniacal ionic solution of zinc alkanoates includes zinc acetate and the most preferred hops plants are varieties of dwarf hops The most preferred aqueous ammoniacal ionic solution of zinc acetate used in the hops enhancement technique of the present invention is marketed under the ACA Concentrate trademark in the United States (available from Platte Chemical Company of Greeley, Colorado) and the Newman's Yeald trademark in Great Britain (available from Newman Agrochemicals, Cambridge, England) This aqueous ammoniacal ionic solution of zinc acetate is prepared by mixing 33 6 parts of glacial acetic acid with 48 parts of water followed by slow addition to the cooled mixture of 18 4 parts of commercial anhydrous liquid ammonia, while maintaining the temperature between 25° and 50°C After cooling the solution to 10°C, 21 8 parts of zinc oxide are slowly added with stirring while maintaining the temperature below 25°C The zinc oxide dissolved rapidly, resulting in a 15-0-0-17 5 Zn solution Eight hundred ml of Newman's Yeald was added to 1000 liters water to produce a fertilizer solution applied in the hop yard at a rate of four liters per cutting The effectiveness of other fertilizer solutions was also evaluated by applicants Some hops cuttings were treated with a balanced 3-0 6-2 5 fertilizer available from Maxicrop International Ltd of Northamptonshire, England under the tradename Maxicrop Triple, with 3 33 liters of Maxicrop Triple added to 1000 liters of water to produce the fertilizer solution used Other hops cuttings were treated with a 8-8-6 fertilizer containing EDTA chelated metals in trace amounts (iron 0 015%, copper 0 007%, manganese 0 13% and zinc 0 005%), available from Hortichem of Wiltshire, England, under the tradename Polyverdol, with 8 liters of Polyverdol diluted with 1000 liters water to produce the fertilizer solution used Still other hops cuttings were treated with a balanced 9-9-12 fertilizer available from Kemira Ltd of

Cheshire, England, with 20 liters of Kemira diluted with 1000 liters of water to make the fertilizer solution used Another group of hops cuttings were treated with Fertileader Arbo, (3-0-0) containing 0 3% zinc in an ammo acid complex, available from Timac U K Ltd of England, with 3 33 liters of Fertileader Arbo added to 1000 liters of water A control group of hops cuttings were not treated with fertilizers

Misted cuttings approximately 6 centimeters in diameter of the Dwarf hop variety First Gold were planted by hand on June 19^th, 1996 in rows 2 2 meters apart, with 1 meter between plants The ground in which the cuttings were planted was well-prepared, with rows marked out with ranging poles Alternate planting positions were marked using either small canes or indentations in the soil surface A hole approximately 8"x8"x8" was dug for each plant and filled with water Normally 4 liters of water was required to fill each hole, a technique referred to herein as drenching, and care was taken to not puddle the surrounding soil surface To ensure that the cuttings would undergo the minimum of stress from the time they were carried from the greenhouse and planted, a handful of pre-wetted potting and bedding compost was placed in the bottom of each hole as soon as the water had subsided from the hole Small pots containing the cuttings were planted by pushing against the up-slope side of the hole, with the top of the pot three to four inches below the surrounding soil level It was considered important that the crowns of the plants be sufficiently deep, as shallow plantings may cause deaths from Fusanum Canker The replaced soil was then carefully firmed by foot To prevent moisture loss, moist soil firmed into the planting hole was mulched using at least an inch of dry soil Comparison cuttings were planted using machine-assisted planting techniques in rows adjacent the hand planted rows on June 10th and 21^st, 1996 The Wolf Maxi™ module planting device available from Checchi & Mag of Budicio, Italy, follows lines of the rows made by a preceding water- mjection device which delivers approximately four liters of water per metre traveled, to a depth of about ten inches Pots containing cuttings were fed into V-shaped cups mounted on a slowly rotating drive wheel and inserted vertically into the soil at pre-set spacmgs As the drive wheel turned, the base of the cup opened to leave the pot behind, after which two small shares and rollers sealed the hole and firmed the soil At planting the soil was dry on the surface yet moist below four inches in depth

All soil was pretreated with base fertilizer, pesticides were applied to all potted cuttings prior to planting, and during the growing season, all plants were treated equally with standard pesticides and sulfur, with one exception A first band spraying of Venzar herbicide over the plant row on the 27th of June was applied at twice the usual rate over the entire experimental area

Also, certain plants, as summarized below, were also treated with eight foliar sprays, which took place on July 2, 10, 15, and 22, August 2, 17 and 26 and September 5 Foliar sprays were applied in the early morning to avoid applications at temperatures at or above 21 °C Plant vigor was assessed as the volume of foliage produced by the plants in the plot Vigor was expressed as a percentage comparison to "standard" plants, which had been planted by hand ten days before in conjunction with planting drenches of the 9-9-12 and the 3-0-0 treatments A summary of the establishment and growth of the hops plants is provided in Table I TABLE

As is apparent from a review of the Table I summary, the hops cuttings treated with the nitrogen/zinc fertilizer in accordance with the present invention exhibited plant vigor throughout the first growing season which was substantially similar to the vigor of cuttings planted nine days earlier by machine. Indeed, within three weeks after planting, the drench treatments of the nitrogen/zinc fertilizer had improved the vigor of the young plants to a level similar to the hops planted by machine nine days earlier. These results achieved by treatment of the hops plants with the applicant's ammoniacal ionic solution of zinc alkanoates were obtained with an individual plant application level of approximately Vz gram of zinc per plant and nitrogen at 4 kg per hectacre Despite this small application amount, the vigor of the cuttings treated with a nitrogen/zinc drench were significantly (i e , p<0 05) more vigorous than where a drench had not been used The vigor exhibited by the hops cuttings treated with the nitrogen/zinc fertilizer having a nitrogen application drench rage of approximately 4 kg nitrogen per hectacre was also similar to hops cuttings treated with a 9-9-12 fertilizer at an application rate of approximately 56 kg nitrogen per hectacre It was noted that the 3-0-0 treatment seriously reduced vigor, perhaps through root scorch, as observed in a planting on a different farm where similar symptoms were observed Two weeks after planting, leaves started to show signs of chlorosis and deformation, and growth of the plants was notably stunted As previous studies had indicated, the foliar sprays did not measurably benefit plant vigor Indeed, a reduction in vigor was recorded throughout the season with the cuttings treated with foliar sprays of the 3-0 6-2 5 fertilizer The greenness of leaves was assessed using similar techniques to assess vigor Generally speaking, the levels of greenness measured correlated well (76%) with the amount of nitrogen that was added by the drench treatments Changes in leaf greenness during July As expected the plants in the treatments not giving any boost in the first three weeks after planting, gave the largest differences The nitrogen/zinc demonstrated high levels of greenness earlier in the season with an intensity that was generally maintained throughout July Greenness evaluations are summarized in Table

TABLE II

Leaf scorch was assessed as the percentage of the existing leaf area which appeared not green and healthy; i.e., the proportion of leaf tissue showing any level of chlorosis. Symptoms of leaf scorch started to show about 10 days after the excessive application of Venzar, peaking at around July 19^th. Less leaf scorch was seen on better-established plants. By the end of July the two foliar spray treatments had shown large increases in the numbers of plants affected. With regard to plant loss, normally a plant loss rate of 2% is the limit of acceptability for dwarf hops Leaf scorch and phytotoxicity data are summarized in Table III

TABLE III

Leaf senescence was assessed, with symptoms of aggravated leaf chlorosis were clearly separable from natural autumn senescence Bine girth was reported as the mean of 6 readings per plot, choosing to ignore both the largest and smallest readings for each plot A Vernier Calliper was used to measure the diameter of the bines at the soil surface, to the nearest 0 01 mm Leaf senescence and bine girth data are summarized in Table IV TABLE IV

The first signs of leaf senescence were seen in the hops planted late by machine and in the hops treated only with a 3-0-0 drench soon after the first two frosts in September. Most leaf senescence occurred in the latter part of October. All treatments had generally reached the same stage of leaf senescence by the end of October. The foliar sprays tended to delay senescence, but the effect was not great. The speed of senescence during October tended to be faster in the early machine plantings and with the nitrogen/zinc fertilizer, indicating that these two were the most reliable methods of prolonging the growing season for plant establishment.

Measurements of bine girth at the end of the season showed clear significant differences between the treatments. The 8-8-6 fertilizer (drench plus foliar sprays), the 9-9-12 fertilizer (drench) and the nitrogen/zinc fertilizer (drench) showed increased girth Bine girth correlated well with both vigor and greenness

As may now be appreciated, the application of a nitrogen/zinc fertilizer to hops cuttings in accordance with the method of the present invention can accelerate the establishment of plants from the cuttings In particular, aqueous ammoniacal ionic solutions of zinc alkanoates, and most preferably ammoniacal ionic solutions of zinc acetates, contribute to the establishment of hops from cuttings In the preferred embodiment, the solution is applied to a hops plant cutting Most preferably, the fertilizer solution is added to a hole which has been dug to receive the hops plant cutting

The method of the present invention has been shown to establish hops plants from cuttings at a rate comparable to cuttings planted by machine more than one week earlier It is possible, then that growers may be able to profitably establish hops plants from cuttings even when the planting of the cuttings is delayed a week The method of the present invention does not require excessive labor, multiple applications of a fertilizer, special techniques or special equipment, and thus is expected to be economical for both small and large hop growing operations

Presently preferred embodiments of the present invention and many of its improvements have been described with a degree of particularity It should be understood that this description has been made by way of preferred examples, and that the invention is defined by the scope of the following claims

Claims

What is claimed is

1 A method of accelerating establishment and growth of a hops plant cutting comprising the step of fertilizing the hops plant cutting with a fertilizer comprising an aqueous ammoniacal ionic solution of zinc alkanoates

2 A method of accelerating establishment and growth of a hops plant cutting according to claim 1 , wherein the method further comprises digging a hole in the soil, pouring the aqueous ammoniacal ionic solution of zinc alkanoates into the hole, placing the cutting in the hole, and filling the hole with soil

3 A method of accelerating establishment and growth of a hops plant cutting according to claim 2, wherein the hops plant cutting is a variety of dwarf hops

4 A method of accelerating establishment and growth of a hops plant cutting according to claim 1 wherein the fertilizer is an aqueous ammoniacal ionic solution of zinc acetate

5 A method of accelerating establishment and growth of a hops plant cutting according to claim 2 wherein the fertilizer is an aqueous ammoniacal ionic solution of zinc acetate

6 A method of accelerating establishment and growth of a hops plant cutting according to claim 3 wherein the fertilizer is an aqueous ammoniacal ionic solution of zinc acetate

7 A method of accelerating establishment and growth of a hops plant cutting according to claim 1 wherein each hops plant cutting is fertilized with at least ^╬¢ gram of zinc

8 A method of accelerating establishment and growth of a hops plant cutting according to claim 2 wherein each hops plant cutting is fertilized with at least gram of zinc

9 A method of accelerating establishment and growth of a hops plant cutting according to claim 3 wherein each hops plant cutting is fertilized with at least gram of zinc.

10 . A method of accelerating establishment and growth of a hops plant cutting according to claim 4 wherein each hops plant cutting is fertilized with at least A gram of zinc.

11. A method of accelerating establishment and growth of a hops plant cutting according to claim 5 wherein each hops plant cutting is fertilized with at least Vz- gram of zinc.

12. A method of accelerating establishment and growth of a hops plant cutting according to claim 6 wherein each hops plant cutting is fertilized with at least Vz- gram of zinc.