Hops are important industrial crops, grown for the harvest of hop cones, which are an essential ingredient for beer production. The cones give beer that classic bitter taste, act as a preservative, and are responsible for the overall taste of the beer. Hops are perennial plants, lasting upwards of 30 years on the same land.
The hop region of Saaz (Žatecko) has favourable farming conditions. The end result is high-quality hops, regarded as a world-wide standard for quality. The most commonly used variety of hops in Czech beer is the Czech Saaz hop, when cross-bread produces varieties such as Agnus, Premiant, Harmonie, Rubín or Sládek.
A year before the hops are planted, the land is fertilized with lime, organic and industrial fertilizers and the soil is thoroughly tilled, as individual layers of soil are meticulously ploughed. Prior to planting, the land is thoroughly dragged and hop poles and wires are set up.
Hops begin to sprout from the ground in March, the stems are plentiful, though they are weak and uneven, and need to be pruned. Pruning consists of cutting the stems and new wood. New shoots are then stronger and more even as there are fewer of them. However, the crops must be treated so as not to damage the old wood, which could lead to the wilting of the entire bine.
Clearing hop fields after the harvest: We cut off remaining vines above the surface of the soil, cut-off parts are then transported and disposed of away from the hop field. Next, the hop fields are dragged using special gates which rid the hop fields of left-over plant parts and hop wire, the waste is disposed of away from the hop field.
Fertilizing the hop field for autumn: Once every three years, we fertilize using organic fertilizers, once every 3-4 years we lime the hop field, and every year we apply an autumn batch of phosphorous, magnesium and potassium fertilizers.
Autumn tillage: Ploughing in between rows using a special mounted reversible plough, allowing for the loosening of compacted soil between rows and for the fertilizer and green manure to settle- necessary for fields heavily infested with weeds. It has a positive effect on the aeration of the soil, development of the soil's microflora, mineralization of nutrients and for root development.
Planting in sparse areas of hop field: Carried out on the basis of the previous inventory of the hop field. Individual hop plants are planted into sparse areas, usually at intervals of 6-7 years.
Dragging the hop field in combination with the spring application of mineral fertilizers: Hop fields are dragged as soon as moisture conditions allow. This field is roughly levelled, and the spring load of fertilizer is spread out. Next we drag the fields, allowing for the loosening and smoothing of the soil's surface and for the fertilizer to settle into the soil.
Mechanized cutting: An essential process during spring. New wood sprouts and partially lateral rhizomes are cut off from the hop bine. In doing so, the bine will keep the desired shape and depth and prevent it from sprawling sideways. This is carried out in the month of April, the exact date depends on the location, variety, age of the hop field and organizational aspects.
Implementation of hop poles and wires: Implementing hop poles and wires is necessary immediately after spring cutting and must be finished by the 10th of May at the latest. Steel wires are used: the upper part of the wire is reinforced with an oblong hop pole using hooks, the lower part of the wire is fastened into the soil beside the plant using stakes in the direction of the rows. We hang 2 hop support systems for every plant vertically in the shape of the letter “V”, opening from the row.
Planting the hops: This takes place roughly in mid-May. It is still done by hand: from one plant, we select shoots that are of the same length, medium size, healthy and undamaged, growing from the middle of the plant, which we wrap around the hop pole clockwise. We wrap about 2-3 shoots onto every hop pole. Second planting (corrective) is carried out at a height of 130-150 cm, where damaged shoots are replaced with spare or late sprouts. During the third planting (inspectional), plants at a height of 200 cm are checked for the winding of the stems (first ten days in June).
Cultivating the hop field: After the hops have been planted and have reached a height of 170-200 cm, we add another layer of soil. An additional layer of soil may be added for plants 500-600 cm in height. We plough in between rows 2-3 times as needed using a chisel plough. Cultivation can also include the use of herbicides.
Summer application of herbicides: In July we kill sprouted and grown-in weeds in rows of plants where they cannot be liquidated with cultivating equipment. If necessary, at the end of June, we arrange for the chemical treatment of late blooming hop plants. At the end of July until the beginning of August, we carry out summer desiccation of the hop fields (killing the bottom herbaceous layers).
Re-planting bent tops of plants, hanging fallen plants: In case of high wind or summer storms, tops of plants may be bent, damaged, or fall off. This type of work is carried out when necessary, up to several times during the growing season until the harvest. Bent shoots are re-planted from the ground using a short stick for smaller plants, and using an adjustable mobile platform for taller plants.
Fertilization during the growing season: We apply primarily nitrogenous fertilizers (prior to ploughing and sprouting) and other missing nutrients, identified by an herbaceous analysis. We also apply foliar nutrients.
Protection of hops against diseases and pests: This is a very crucial step, which must be carried out meticulously, as it significantly impacts the yield and quantity of hop cones. These measures are carried out in accordance with the methodological guide for the protection of hops.
Hop irrigation: Hops have an increased demand for water during two periods- sprouting to the first phases of flowering (1st half of July), cone formation period (end of July to mid-August). If there is weak precipitation during these periods, additional irrigation is necessary.
The hop harvest takes place after hops have reached technical maturity- the cones are closed, supple when pressed, are of a yellow-green colour with a natural shine and have high lupulin content and typical subtle hop aroma. The beginning of the harvest falls roughly on the period after August 20th, optimal maturity occurs approximately between the 25th and 28th of August, and the harvest should be completed within 14-16 days. The harvest is carried out mechanically in two phases.
In the 1st phase, hop plants are cut 100-130 cm above ground, plucked either manually or using a tractor's mounted corn picker, loaded onto the hop trailer, and transported to a stationary combing machine. Transported plants must be fresh and turgid and the interval between cutting and combing must be as short as possible, otherwise the hop cones may be damaged during combing. The transport of the plants and combing must be coordinated, as the plants cannot be cut and stored for later use.
In the 2nd phase, the hop cones are separated from other parts of the plant using a combing machine, waste from leaves and vines are transported to a compost heap. Proper regulation of the combing machine reduces the risk of cone damage, reduces the number of impurities and reduces the amount of losses during the combing process.
In mechanical terms, the company is self-sufficient regarding the harvest of hops and grains. The harvest of cereal and rapeseed is carried out using two Massey Fergusson harvesters- modern harvesters from a global brand. These harvesters leave the fields clean and effectively harvest the crops without any losses. Grains are harvested using two harvesters and three haulers. All of the harvested crops are immediately transported to the buyer.
Harvesting hops requires nine combing machines and six belt dryers. Tractors with plucking devices can pluck the hop vines directly from the field and transport them to the picking line. Here, the shrubs are hung up on the combing line and drawn into the combing machine, where after a series of technical procedures, the hop cones are separated from leaves and vines.
Stripped hops can breathe easily and generate heat and moisture. Due to the risk of overheating or even spoilage (loss of shine, change of colour, negative impact on the overall quality of the cones), hops must be quickly transported to the drying room.
The interval between combing and drying the hops should not exceed 2 hours- at longer intervals it is necessary to ensure aeration. For this reason, it is necessary to coordinate the combing and drying processes.
Drying is done either in drying rooms or on belt dryers for 6-9 hours. During the drying process, it is crucial that there is a sufficient amount of air circulation and an efficient venting system for the released moisture in order to prevent the hop cones from overheating.
Dried hop cones are brittle, they are susceptible to damage and crumbling, and cannot be handled further. It is therefore necessary to adjust humidity levels. This can be achieved either by allowing the cones to accept atmospheric moisture naturally in a period of 2-4 weeks (spreading out hop cones into shallow layers, carefully turning them over, and spraying them if necessary) or using special equipment – in a climatic chamber. Climatic chambers are usually connected to belt dryers.
These cones are immediately packaged into transport bales, weighing 60-70 kg. Each bale is individually weighed, labeled with the necessary information, sealed at the top and properly recorded. Packaged cones are then transported to the central warehouse.
In the central warehouse, the hops are sampled and verified- necessary procedures for international export. The quality of the cones is assessed by a laboratory analysis and subjective assessment, wherein an average sample from the batch is compared with a prototypical sample. A chemical analysis of the content of alpha acids, moisture or mildew particles in the hops is carried out by the Hop Research Institute in Saaz.
The final price of the hops is then determined on the basis of both partial assessments (classification). When the hops and documentation are prepared, the employees of the Gorky warehouse in Saaz load the hops into a truck and transport it for further processing to the Joh. Barth Company in Sant Johann.