
Humulus lupulus
Humulus lupulus
Safety & Hazards
Skin contact with the plant causes dermatitis in sensitive people[1]. Hops dermatitis has long been recognized. Not only hands and face, but legs have suffered purpuric eruptions due to hop picking. Although only 1 in 3,000 workers is estimated to be treated, one in 30 are believed to suffer dermatitis[2]. Dislodged hairs from the plant can irritate the eyes[1].
Cultivation Details
Easily grown in a good garden soil in sun or semi-shade[3, 4]. Prefers a deep rich loam[5] and a warm sheltered position[6]. Plants can succeed in dry shade if plenty of humus is incorporated into the soil, once established they are also somewhat drought tolerant[7]. Hops are reported to tolerate an annual precipitation of between 31 and 137cm, an annual temperature in the range of 5.6 to 21.3°C and a pH of 4.5 to 8.2[2]. Plants are very hardy tolerating temperatures down to about -20°c when dormant[6]. The young shoots in spring, however, can be damaged by any more than a mild frost[2]. A climbing plant, supporting itself by twining around the branches of other plants[8]. Hops are frequently cultivated, both commercially and on a domestic scale, in temperate zones for their seed heads which have many medicinal qualities and are also used as a flavouring and preservative in beer. There are many named varieties[9]. They grow best between the latitudes of 35 - 51°N and 34 - 43°S, with mean summer temperatures of 16 - 18°C[2]. Generally, for beer making, the unfertilized seed heads are preferred and so most male plants are weeded out[10]. Hops are fairly deep rooted, but with a network of shallow feeding roots. These horizontal feeding roots spread out at depth of 20 - 30 cm in the soil and give rise to fibrous roots in upper layers of soil[2]. The vertical roots develop downwards to a depth of about 150 cm with a spread of 183 - 244 cm and have no fibrous roots[2]. The bruised leaves are refreshingly aromatic whilst the flowers cast a pleasing scent[11]. A food plant for many caterpillars[12]. A dioecious species - both male and female forms must be grown if fruit and seed are required.
Propagation
Seed - sow spring in a cold frame[5]. Germination is fairly quick. Prick out the seedlings into individual pots as soon as they are large enough to handle and plant out in the summer or following spring. Division in spring as new growth begins[3]. Very easy, you can plant the divisions straight out into their permanent positions if required[PFAF]. Basal cuttings in early spring. Harvest the shoots when they are about 10 - 15cm long with plenty of underground stem. Pot them up into individual pots and keep them in light shade in a cold frame or greenhouse until they are rooting well. Plant them out in the summer. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Humulus+lupulus>
Pollinators
Wind
References
- [1]A Field Guide to Medicinal Plants. Eastern and Central N. America. — Foster. S. & Duke. J. A. · Houghton Mifflin Co. · 1990 · ISBN 0395467225 ↩︎A concise book dealing with almost 500 species. A line drawing of each plant is included plus colour photographs of about 100 species. Very good as a field guide, it only gives brief details about the plants medicinal properties.
- [2]Handbook of Energy Crops — Duke. J. · - · 1983 · https://hort.purdue.edu/newcrop/duke_energy/dukeindex.html · ISBN - ↩︎Published only on the Internet, excellent information on a wide range of both temperate and tropical plants.
- [3]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
- [4]The Wild Garden. — De. Bray. L. ↩︎Interesting reading.
- [5]The Gardener's Assistant. — Thompson. B. · Blackie and Son. · 1878 · ISBN - ↩︎Excellent general but extensive guide to gardening practices in the 19th century. A very good section on fruits and vegetables with many little known species.
- [6]Perennials. Volumes 1 and 2. — Phillips. R. & Rix. M. · Pan Books · 1991 · ISBN 0-330-30936-9 ↩︎Photographs of over 3,000 species and cultivars of ornamental plants together with brief cultivation notes, details of habitat etc.
- [7]The Dry Garden. — Chatto. B. · Dent · 1982 · ISBN 0460045512 ↩︎A good list of drought resistant plants with details on how to grow them.
- [8]Gardening on Walls — Grey-Wilson. C. & Matthews. V. · Collins · 1983 · ISBN 0-00-219220-0 ↩︎A nice little book about plants for growing against walls and a small section on plants that can grow in walls.
- [9]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · Kampong Publications · 1990 · ISBN 0-9628087-0-9 ↩︎Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.
- [10]A Modern Herbal. — Grieve. · Penguin · 1984 · ISBN 0-14-046-440-9 ↩︎Not so modern (1930's?) but lots of information, mainly temperate plants.
- [11]Scented Flora of the World. — Genders. R. · Robert Hale. London. · 1994 · ISBN 0-7090-5440-8 ↩︎An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.
- [12]Butterflies and Moths in Britain and Europe. — Carter D. · Pan · 1982 · ISBN 0-330-26642-x ↩︎An excellent book on Lepidoptera, it also lists their favourite food plants.
- [13]Encyclopaedia of Medicinal Plants. — Chiej. R. · MacDonald · 1984 · ISBN 0-356-10541-5 ↩︎Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
- [14]Sturtevant's Edible Plants of the World. — Hedrick. U. P. · Dover Publications · 1972 · ISBN 0-486-20459-6 ↩︎Lots of entries, quite a lot of information in most entries and references.
- [15]Food for Free. — Mabey. R. · Collins · 1974 · ISBN 0-00-219060-5 ↩︎Edible wild plants found in Britain. Fairly comprehensive, very few pictures and rather optimistic on the desirability of some of the plants.
- [16]Edible and Medicinal Plants. — Launert. E. · Hamlyn · 1981 · ISBN 0-600-37216-2 ↩︎Covers plants in Europe. a drawing of each plant, quite a bit of interesting information.
- [17]Rare Vegetables for Garden and Table. — Organ. J. · Faber · 1960 · ISBN - ↩︎Unusual vegetables that can be grown outdoors in Britain. A good guide.
- [18]Britain's Wild Larder. — Loewenfeld. C. and Back. P. · David & Charles; Newton Abbot. · ISBN 0-7153-7971-2 ↩︎A handy pocket guide.
- [19]Medicinal Plants of China — Duke. J. A. and Ayensu. E. S. · Reference Publications, Inc. · 1985 · ISBN 0-917256-20-4 ↩︎Details of over 1,200 medicinal plants of China and brief details of their uses. Often includes an analysis, or at least a list of constituents. Heavy going if you are not into the subject.
- [20]The Encyclopedia of Medicinal Plants — Chevallier. A. · Dorling Kindersley. London · 1996 · ISBN 9-780751-303148 ↩︎An excellent guide to over 500 of the more well known medicinal herbs from around the world.
- [21]The Herb Book. — Lust. J. · Bantam books · 1983 · ISBN 0-553-23827-2 ↩︎Lots of information tightly crammed into a fairly small book.
- [22]Dictionary of Economic Plants. — Uphof. J. C. Th. · Weinheim · 1959 · ISBN - ↩︎An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.
- [23]The Dictionary of Modern Herbalism. — Mills. S. Y. ↩︎An excellent small herbal.
- [24]Narcotic Plants — Emboden. W. · Studio Vista · 1979 · ISBN 0-289-70864-8 ↩︎A lot of details about the history, chemistry and use of narcotic plants, including hallucinogens, stimulants, inebriants and hypnotics.
- [25]Earth Medicine, Earth Food. — Weiner. M. A. · Ballantine Books · 1980 · ISBN 0-449-90589-6 ↩︎A nice book to read though it is difficult to look up individual plants since the book is divided into separate sections dealing with the different medicinal uses plus a section on edible plants. Common names are used instead of botanical.
- [26]Encyclopaedia of Herbs and their Uses. — Bown. D. · Dorling Kindersley, London. · 1995 · ISBN 0-7513-020-31 ↩︎A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.
- [27]Glossary of Indian Medicinal Plants (Including the Supplement). — Chopra. R. N., Nayar. S. L. and Chopra. I. C. · Council of Scientific and Industrial Research, New Delhi. · 1986 · ISBN - ↩︎Very terse details of medicinal uses of plants with a wide range of references and details of research into the plants chemistry. Not for the casual reader.
- [28]Flowers of Europe - A Field Guide. — Polunin. O. · Oxford University Press · 1969 · ISBN 0192176218 ↩︎An excellent and well illustrated pocket guide for those with very large pockets. Also gives some details on plant uses.
- [29]The Useful Plants of Great Britain. — Johnson. C. P. ↩︎Written about a hundred years ago, but still a very good guide to the useful plants of Britain.
- [30]Plant Fibres for Papermaking. — Bell. L. A. · Liliaceae Press · 1988 · ISBN - ↩︎A good practical section on how to make paper on a small scale plus details of about 75 species (quite a few of them tropical) that can be used.
- [PFAF]Plants for a Future — pfaf.org ↩︎