Hops - an ancient but new herb
There are so many herbs that have been part of the western diet for centuries that we assume all of our current crops are that old. Hops are a key ingredient of beer for taste, aroma and preservation and beer seems to have been part of our diet since forever. So one assumes that hops have also been around for ages. However they were assumed to be of no medicinal, commercial or dietary value until the 14th or 15th centuries when their antimicrobial properties were first noticed. During the 16th century it became a key component of beer production in Europe. From there its medicinal properties were discovered and it quickly entered the panacea of medicinal herbs.
Hops is a twining herb native to Europe with a very particular growing region. They are a member of the Cannabaceae family (same as Cannabis or Marijuana) and contain a variety of oils that give them their unique properties. For hops to perform at their best they need at least 15 hours of daylight which occurs at latitudes of 35o or above. However they also need a frost free spring. As they are fully deciduous winter cold is not an issue - -20o is quite acceptable. However spring frosts can have a nasty effect on the rapidly growing young tips.
There are both male and female plants with only the female needed for ‘hop’ production and must remain unpollinated to give the best cones. Both sexes needed for seed production and the resultant oils. The female plants produce the long chains of hop flowers that are so useful in beer production.
Although the plants are extremely grow and tolerate a wide range of conditions they are particular in how they grow. As a plant they will live for up to fifty years. Each year they will die back to a simple rhizome after the first few frosts. In early spring they will produce soft new growing tips, These will grow straight up until summer solstice reaching heights of 7+ m. They twine around their supporting structure (as such they are called ‘bines’) in a clockwise direction in following the daily movement of the sun.
After the solstice they produce lateral growth stems which in turn produce the hope cones when the autumn equinox occurs. The post equinox flowering means they are referred to as short day plants. By mid autumn the cones are staring to ripen and dry out and the lupulin oil is maturing. At this time the hops are picked, dried and processed. The flowering is day length dependent but also requires a set number of above ground nodes which require a certain bine length – actually certain number of nodes.
In their natural environment they are at the forest edges with access to ample water, and will reach a height of up to 7–8 m. To attain this size in their limited growth period the rate per day of the aerial parts can reach 30 cm. The total area covered by the leaves can reach 20 square meters with a length of the roots that can reach up to100 m in one growing season.
Hops is one of the world’s most important crops. Not because it will solve any major disease, not because it will help feed the world but because it is a key ingredient in the flavour component of beer. Mention the word hops to an Australian and you conjure up images of icy cold beer with a golden colour and frothy white head. Mention to a UK gardener and they imagine rapid growing climbers with interesting flowers. The beer connection is quick and obvious even though very few people actually know how or why hops are used.
The plant has been in cultivation for over 10,000 years and originates from south east Asia. It made its way to Europe around 1000 years ago and in to the UK around the 15th century. They add the ‘bitter’ flavour and also act as a preservative against many bacteria in the fermentation process. Over the last few thousand years many cultivars have been selected for a mixture of flavour styles and for growing conditions. With the surge in popularity of Craft Beers there has been a parallel demand for hops and for new varieties.
There are the old world varieties coming from Germany and Eastern Europe. Then there are the New World varieties from Australia and New Zealand. Finally some of the leading edge breeding is coming out of north eastern USA. Unfortunately due to the range of diseases carried by Hops and the importance of the crops to the Australian economy the new varieties are very hard to import. Indeed the costs of bringing in one plant are in excess of $2500 – if there are no problems.
As mentioned above most Australians think of hops for their use in beer production but historically they have had a much wider use in the domestic and commercial garden. In Europe they are popular as an ornamental climber that gives colour and form to the home garden. They are quick growers and have attractive foliage and flowers. They were used classically to surround doorways and arches. The flowers are great for beer production but the roots and leaves can be used to add flavour to salads and baked dishes.
As with so many modern garden plants, Hops have a long history as a medicinal herb. There are at least a dozen or so studies into the health benefits from consuming various parts of the hops plant. The main positive is related to their early use in beer production. That is they have a fairly potent anti-microbial properties which, prior to the evolution of current antibiotics was an important characteristic.
Hops are much like lavender in requiring long periods of daylight with little effect from temperature. To get enough light they need to be grown south of central NSW. Like lavender they also prefer to be mounded to aid in drainage and root control. Historically Hops are planted out as rhizomes in late winter however they perform just as well when planted as living, growing plants in spring/summer. They like to be planted in 18cm high mounded rows running in an east west direction giving the plants maximum exposure to the sun. Hops are deciduous and die back to a below ground rhizome in late autumn.
On one hand Hops plants are really easy to grow and require little care or effort on the other hand when grown for hop production there are a few simple processes. Hops are a “bine” and produce rapidly growing climbing stems that should be grown up ‘string lines’ for best results. The strings should be around 4 to 5m long. After planting (and each spring) choose the three strongest shoots and train them anticlockwise up the string. They need regular watering (around 5 litres per day) which is best delivered through a drip system. They respond to high nitrogenous fertiliser and a pH of 6 to 7. Trim off leaves from bottom 75cm to improve plant health.
Like growing, harvesting is fairly simple but requires some basic processes. The flowers will appear in late January and grow through to early autumn. When the flowers have a dry papery texture and are just starting to go brown they are ready for harvest. After harvest they should be dried and vacuumed sealed for future use. After a year or two one plant should give enough hop flowers for several brews. Once the plants are established the passionate home brewer can start making their own blends.
There are hundreds of hop varieties around the world. Some are 500 plus years old and others are less than a year in production. Each continent is known for its own particular flavours and aromas. The number of varieties in Australia is much less than the rest of the world as hops is a regulated import and must undergo significant quarantine processes. We have started collecting different cultivars and as we get them into production I will put details on their characteristics, cultivation and use.
Pride of Ringwood