The Cranberry of commerce (Vaccinium macrorarpon) is a small evergreen plant native to eastern and northeastern North America, creeping over the ground with rooting runners about 3 ft. long and bearing upright branches about 6 in. tall on which the fruits are borne in the fall. Cranberries are produced commercially in Mass., Wisc., N.J., Wash. and Ore. with present annual estimates for the states in the above order of 573,000 barrels, 400,000 barrels, 159,000 barrels, 66,000 barrels, and 139,000 barrels, for a total U.S. crop of 1,337,000 barrels. A barrel of cranberries weighs about 100 lbs.
It has been estimated that 25% of the crop is sold as fresh fruit, and there is a tendency for this to show a slow but rather steady decline, year by year. About 25% of the crop is used in making cranberry juice cocktail and this market is steadily and almost rapidly increasing. The remaining 50% of the crop is sold as strained and whole-berry sauces, cranberry-orange relish and various other products. It is of interest to know that one of the large grower-owned Massachusetts cooperative-selling organizations handled 85% of the U.S. crop in 1964 with gross sales of $45,000,000.
This huge industry is centered on the small farms on and near Cape Cod. It is here that soil and water conditions, combined with just the right climate, are ideal for cranberry production. The home gardener does not customarily make his own cranberry bog so a quick description here of the methods used for producing cranberries commercially will be sufficient.
The cranberry planting must be in a bog or similar area where there is plenty of acid water, and arrangements must be made so that the bog can be flooded with this water at an31 time. This usually means there must be facilities for storing large amounts of water at a higher level than the bog or that there is a stream with ample water of the right kind and it can be pumped to flood the bog. Flooding is necessary for the good growth of the plants, to aid in insect control, and to aid in frost protection as well as to keep the plants from being injured by winter cold. The soil must be acid, preferably of a pH of 4.5-5.0. If one looks around carefully near a cranberry bog one will find growing naturally on cranberry soils.
Since accurate flooding of the bog is essential, it should be on flat land, with all the miscellaneous weed plants removed. It is also necessary to have facilities for draining the bog rather promptly, for if it is flooded when the plants are growing, the water should not be allowed to remain on the plants for more than 24 hours. This then necessitates a series of drains and ditches and a low spot where the water can runoff at the proper time.
In preparing the soil, the final operation is to apply 3-4 in. of sand over the entire bog area, for it is in this that the new cuttings are stuck. The sand acts as mulch and reduces water loss from the soil, aids in restraining weed growth and in the early spring and fall when danger from frost is imminent, it gives off some heat at night and so aids somewhat in frost protection. It should have a pH of 4.5.
Cuttings are taken just before growth starts in the spring. In order to do this a well-grown stand is mowed or cut with a scythe and the clippings stuck in the soil at 10-in. intervals each way, usually 2-3 per hill. Some growers merely broadcast the clippings and disc them in but this takes a great deal more cuttings than is normally necessary. Setting out cuttings is done in late April, May or June but usually May is best.
After planting, the bog is flooded for a day or two so that the water will firm the cuttings in place, then drained and of course weeded for the remainder of the summer. Normally the planting will bear its first crop the 4th year. After picking, the longest upright branches are cut back and a covering of sand about s in. deep is placed over the field to aid in the roots becoming well established. Then the bog is flooded to just above the tops of the plants for the winter. Flooding is usually done in Mass., about Dec. or whenever the sand remains frozen all day, and the bog is drained in May.
Flooding the bog is sometimes necessary in late spring after growth has started to prevent the young buds from being killed by late frosts. Usually a partial flooding only is necessary, for the water will give of a certain amount of heat at night. It is obvious to see then why quick flooding and draining are necessary. Flooding is sometimes used as a means of controlling insect pests and in the early fall is also needed to protect a crop from freezing. Picking usually starts in Mass., on Labor Day and continues until around Oct. 20.
The bog is resanded at intervals every 3-4 yrs., applying anywhere from 1-4. in. of sand depending on circumstances.
It is these two varieties that make up 93% of the acreage in Mass. ‘Me Farlin’ is the chief variety on the Pacific Coast, and in Wisc. ‘Me Farlirt’, ‘Bennett’ and ‘Searr’ are the most important. Of course, there are other varieties being introduced and tried, but these are the ones most used at present. It is also important that only one variety be planted to a bog where flooding is done all atone time, for varietal differences in growth, ripening periods and disease resistance are such that more than this is impractical.
Picking the berries is usually done with scoops by hand or sometimes by machine. The berries are collected in boxes and taken to the canneries where the chaff is blown out and the good berries sorted from the bad. At present, most of the “fresh” crop is sold and used by Christmas. The business is one that has been growing in recent years, since more and more uses for cranberries and their products are being strenuously advertised by the large growers’ cooperatives.
Cranberry growing is a commercial operation requiring specific equipment and expert knowledge and not a home garden activity. Expert advice from local authorities on pest control is advised.
Cranberry Insect Pests
Cranberry fruit worm which cats the berries and black-headed or other fire worms which kill leaves and flowers are among the most destructive. Span worms and gypsy moth which eat the leaves and girdler which destroys the stems are locally important. Blunt-nosed leafhopper, the vector of false blossom disease must be controlled. Flooding and intensive use of insecticides are the recognized control treatments.