POP CORN: A Marlborough Venture

New Zealand Journal of Agriculture, Volume 82, Issue 1, 15 January 1951, Page 38

POP CORN: A Marlborough Venture

By

S. FREW,

Orchard Instructor,

Department of Agriculture, Blenheim.

TJOR many years pop corn has been known in New *• Zealand, usually as a novelty form of foodstuff made up as an attractive confectionery, sold generally at booths at agricultural and pastoral shows and holiday resorts. Recently, however, the industry has been placed on a more substantial footing, and the production of a suitable corn for this trade, and its subsequent processing, has been the successful venture of a small group of Marlborough farmers and businessmen. The story of this development is interesting and gives a further proof that initiative, painstaking trouble, and confidence of success in new fields are still qualities to be found in New Zealanders.

THE production of pop corn in Marlborough was first introduced by Mr. R. A. McPherson, of Blenheim, who, knowing the tremendous expansion and ramifications of the business in the United States of America, saw possibilities in the development of both the growing and processing of pop corn in New Zealand. Taking into account the fact that the Marlborough climate approximated that of the corn belts of the United States, he decided to grow a small trial crop. In 1945 he obtained his first small sample of good hybrid corn seed from the United States and planted it in his back garden. Results were so encouraging that the next year he imported a larger quantity of seed, sufficient to grow a series of trial areas.

Several Varieties Tried

Several varieties were tried and various locations used, the object being not only to determine which varieties were best adapted to local growing conditions, but which type of land would prove most suitable. Results on this occasion were not so uniformly good, but much was learned from the fairly extensive trial plots. One 2-acre block, for various reasons, proved a complete failure, but the knowledge gained enabled similar mistakes to be avoided in future. In some instances, however, the results were very satisfactory, the yield often far exceeding comparable yields in the United States, and the quality of the corn was excellent.

Mr. McPherson’s partner in the first trials was Mr. H. Charleston, a Blenheim business man, while Mr. J. Broughan, a Blenheim farmer, showed a truly venturesome spirit in agreeing in 1946 to devote some of his valuable land to this unconventional crop, and his wide knowledge of local conditions and lifetime farming experience were invaluable to the partners in these early stages.

The product from the trial plots was processed in a little room at the back of Mr. Charleston’s brush factory in Blenheim, a frying pan being used to pop the corn. The pop corn was then laboriously coloured, sweetened, and packed into transparent cellulose packets by hand, and late in 1946 the market was tested out with this small parcel of processed corn. Its immediate success and the insatiable demand from the trade for further supplies convinced the originators of the scheme that they could expand and consolidate their business with confidence, and from that date, although further trials were still being made, the initial experimental stage could be said to have concluded successfully.

Early Difficulties

During this stage setbacks and difficulties were experienced in the factory as well as in the field. Shortages of sugar and other materials used for processing had to be overcome, permission to import better equipment obtained, labour trained for the factory work, and methods of handling revised or discarded. During this period also results from trial areas were tabulated and checked with painstaking thoroughness. But with these difficulties successfully passed commercial production was begun, at first, in a small way only.

First Commercial Production

In 1947 a total of 4 acres was planted on Mr. J. Broughan’s property. Already the likely varieties in the trial ■ plots had been checked for production per acre, popping expansion, maturity dates, and general suitability for local conditions, and a supply of specially crossed seed of the most promising varieties ordered from the United States. The resultant yield was outstandingly good and the processing of this crop enabled the small factory to keep producing fairly steadily for a while. Supplies, however, were still wholly inadequate for the demand and arrangements had to be made to import corn for popping in order to keep the factory going and to fulfil at least a proportion of the orders outstanding. The imported corn proved quite inferior to the local product and it was realised that a

substantial increase in acreage locally would have to be planned if importations were to be avoided and the high quality of the local product maintained.

Increased supplies of the specially crossed seed were therefore ordered for the 1948 growing season and in that year a total of 40 acres was devoted to the crop, while for the 1949-50 and subsequent seasons a total of 80 acres has been the objective. Production of Hybrid Seed

The steady expansion of the industry in Marlborough has brought its special problems, an important one being the availability of seed for the increasing area planted. Until 1949, seed was imported from America, and not only was this a costly business involving dollar expenditure, but continuity of supply was uncertain. All high-quality pop corn seed comes from a carefully bred hybrid plant, but to use secondyear hybrid seed for production of plants would be to court disaster, and a very low yield of inferior corn might result. It was felt therefore that the time had arrived when the work of hybridisation should be undertaken locally in order to ensure supplies of seed and retain those varieties which have proved so satisfactory. In the United States innumerable crosses have been made in the breeding of special varieties, but there are four main parent varieties suited to New Zealand conditions and a further three are being subjected to further trials. Originally, production was carried on with an imported hybrid produced from two of these strains. A small supply of seed of the seven strains suited to New Zealand conditions was, however, imported in 1948. As only a few seeds of each variety were available, cross-pollination and the production of hybrid seed on a large scale could not be attempted immediately and the first year had to be devoted to increasing the amount of parent seed. To ensure purity of strain the different varieties. of seed were grown in the first year in isolated areas and hand self-pollination of all plants was undertaken. This meant the placing

of bags over all tassels to collect the pollen and the covering of all ear shoots to prevent contamination from other sources; 3000 specially manufactured bags were used for the purpose. When the ear shoots reached the correct stage for the reception of pollen the bags over the tassels were removed and the pollen transferred to the silk on the ear shoot. Thus per-

petuation of the true parent varieties was assured and a good supply of seed is available for hybridising. Actually the work has to be done each year if the parent strains are to be retained and never can the whole of the available seed be used for the production of hybrid seed. For the actual hybridising cross-pol-lination is encouraged by the field planting of alternate rows of the two parent strains. The resultant seed will then be stock seed for planting out pop corn areas the following year. Since the 1949-50 planting season sufficient hybrid seed has been available in Marlborough for all New Zealand production requirements. Climate and Soil Results from the trials made in Blenheim demonstrated clearly that the Marlborough climate was particularly suited to this type of crop. The prerequisite for successful corn production is a dry autumn, enabling the seed to dry out to the requisite moisture content for successful popping. A low humidity is therefore essential and few parts of New Zealand could be considered as satisfactory as Marlborough in this respect. The danger of early frosts, is, however, a possible disadvantage and this has to be countered by growing early or quickmaturing varieties. The trials also illustrated the need for careful selection of growing sites and soil types. The corn plant will not flourish in wet conditions and good drainage and a warm soil are necessary. A heavy type

of soil is useless and the best results were obtained on a sandy‘ silt loam of good depth with a free subsoil. Such land is available in Marlborough in many localities and in every way this district seems to have unique advantages for pop corn culture.

Types of Corn

The development of corn hybrids has been an important work in the United States during the past 30 years and today their strains are outstanding, improved varieties having been bred for all corn-growing areas. Not only have strains been produced which give greatly increased yields and resistance to stalk breaking, but varieties with regulated maturity dates have been tabulated and it is possible now to get a strain or variety with a short- or long-growing period as required. The main factor with improved American strains, however, has been the increase in the popping expansion rate. Old varieties of corn had a popping expansion ratio of approximately 15:1, but with several of the latest strains this ratio has been increased to 32:1 (that is, the corn will expand after popping to 32 times its original size).

Naturally the economic variety to grow is the one with the greatest volume per acre of popped corn, not necessarily the variety with the highest popping expansion. This, therefore, was one of the main objects of investigation in the local trials, and of the varieties found to grow best under local conditions seven were selected which complied with the qualification. Actually, most of them have a popping expansion ratio of approximately 30 : 1 and this together with their heavy production of seed per acre ensures a high yield of high-quality corn.

Pop Corn Culture

With the industry now in full-scale production, the rather crude methods previously adopted in the field have been superseded, but in the beginning the culture of pop corn was on simple lines, the salient features being as follows:—

Sowing: After a deep autumn ploughing the land is worked to a fine tilth in spring and sowing begun at the end of October, when the risk of latespring frosts is over. One of the

simplest and most successful methods has been that employed by Mr. Broughan, who drilled in the seed, in rows 28in. apart, with reverted superphosphate. An ingenious disc with holes at regular intervals, replacing the stars in the drill, also sowed the seed successfully and at fairly even spacings. Another area was sown by hand, three seeds being sown together at 3ft. intervals with 3ft. between the rows. This method, although laborious, resulted in a rowed crop which could be cultivated both ways, a decided advantage over drilled seed, where weed growth could not be eradicated in the rows. American authorities favour the regularly spaced, row-crop method, allowing cross-cultivation, and claim that increased production may be expected from this system. Though little difference in crop weight has been noticed here, this method is now recommended because of the better control of weeds achieved. It is hoped to obtain a proper corn planter for the use of local growers for next

season’s sowing. This machine is reputed to drop three seeds at regular intervals in each row and therefore should be ideal. Cultivation: Where seed is sown with the drill subsequent cultivation has been confined to a harrowing while the plants are still small enough not to be injured, but with the spaced sowing, cross-cultivation with a small inter-row cultivator is maintained until fairly late in the growing season. Manuring: In addition to 2cwt. of reverted superphosphate at time of sowing, side dressings of sulphate of ammonia are beneficial, and on most types of land a substantial dressing of lime is required to produce satisfactory crops. Diseases: Very little trouble has been experienced with disease. Caterpillars, identified as the corn earworm or tomato caterpillar, have been noticed in isolated instances, but so far the percentage of plants affected is too small to cause alarm and, moreover, the caterpillar appears to attack

the cob too late to cause serious damage. In some areas grass-grub has taken occasional plants.

Harvesting: While the growing of pop corn was in the experimental stages harvesting was done by hand, but this could not be attempted with a large area and it was then that the advantages .of Marlborough’s dry autumn were appreciated. The corn matured perfectly on the plant and a header harvester successfully threshed the seed without damage. American authorities, however, are unanimous in their opinion that the corn is better harvested in the cob, and in 1950, therefore, a mechanical cob harvester was imported. This was found to make an excellent job, up to 4 acres of cobs per day being picked by this means.

Drying of corn: For corn harvested by the header the only drying necessary was to spread the seed over wooden floors for a short period to prevent any risk of mould developing. The most efficient means of drying seed in the cob has been to deposit the cobs in a hop kiln for a few hours.

Moisture content: For successful storage and popping the moisture content of the corn must not exceed 14

tent or me corn must not exueeu jl*± per cent. Fortunately field-ripened corn in . Marlborough has a moisture content of only 15 per cent, when harvested and thus is approaching reasonable storage and popping condition. In most parts of New Zealand this low moisture content could not be obtained in the field and a major difficulty in drying to the correct stage would be encountered. Production per acre: In Marlborough up to 40001 b. per acre has been obtained in some seasons and the average must be at least 30001 b. per acre. Processing: The simple method of the first trial years has now, of course, been superseded by greatly improved equipment. The latest and best popping machines have been imported

and, as these are capable of turning out 25,000 packets per day, production is now reaching large proportions. After being popped with essential oils the corn is immersed momentarily in a bath of colouring and sweetening agents and then packed in attractive transparent cellulose packets. Distribution and sale: The whole of the output from the Marlborough factory has been disposed of through various stores, at first mostly in the North Island districts, but by last year distribution had become Dominion wide. Success Result of Careful Work The success of the local industry is undoubtedly the result of the careful and thorough work done in the initial

stages. Only improved strains of seed, proved suitable for local conditions, have been grown and great care has been taken to . select suitable land for their production. Some of the corn imported in the past has been of comparatively inferior quality and it is pleasing that it can be said definitely that the local product, though being produced at a price comparable with imported lines, appears to be a superior corn in every way and is much sought after by the whole trade. In a small way pop corn is taking its place among the industries which help to make New Zealand self-sup-porting, and full credit must go .to the originators of the scheme for their initiative and enterprise, which so successfully converted this industry from an idea to a reality.