Herb · Cannabaceae
Hops
Humulus lupulus
Given full sun, deep soil, and a tall support to climb, hop bines drive skyward through the season toward a brewing harvest.
Full sun
Every 2–4 days
120–150 days
USDA 3–8
Overview
Hops supply the bitterness and aroma of beer from a climbing perennial that regrows from a persistent crown each year. Its fast shoots, the bines, twine clockwise up any string or trellis, extending as much as 25 feet (7.5 m) in one season before the top growth dies back to the ground in fall. The papery green cones set in late summer are the harvested part.
The species is dioecious, so a given crown is either male or female and only female plants bear the brewing cones. The bines ascend by wrapping their rough, hooked stems around a support rather than by producing tendrils, which is why a tall trellis or twine line is a structural requirement rather than an option. Below ground, tough rhizomes extend the plant laterally, the same habit that lets an unchecked planting colonize a corner of the garden.
Once established the plant is hardy and long-lived, tolerating winter lows near -29°F (-34°C) because the crown survives while the top dies away. The first season goes into root development, and full cone production generally arrives in the second or third year as the crown matures. A female cultivar given height and steady moisture will crop from one crown for many seasons.
Care
The short version: hops need full sun, deep and rich well-drained soil, and steady moisture through the heat of summer, together with a tall support for the bines and ample room so the rhizomes do not run.
Light
Hops require full sun, and greater light yields better results, because the bines depend on long days and high irradiance to fuel their rapid growth and set sound cones. They tolerate a little partial sun, but reduced light produces weaker bines and a diminished harvest.
Water
Water demand peaks in summer, since the bines transpire heavily through June and July during their fastest growth. Hold the soil consistently moist but never waterlogged, then reduce irrigation as the plant dies back in fall.
Soil
Hops perform best in deep, rich, well-drained sandy loam high in organic matter, which suits a deep-rooting, heavy-feeding perennial. Target a soil pH of 6.0 to 6.5.
Temperature
The plant withstands a broad range, surviving winter lows near -29°F (-34°C) and growing well up to roughly 90°F (32°C). Cold seldom injures an established crown, which dies back and regenerates each spring.
Humidity
Outdoor humidity tracks the season, so there is no set point to maintain. Air circulation is the decisive factor, because crowded, damp foliage is precisely the environment in which downy and powdery mildew establish.
Feeding
Apply a balanced fertilizer supplying nitrogen monthly from spring through midsummer during vegetative growth, then taper before cone set. The rapid growth creates a high nutrient demand.
Pruning
In spring, cut second- and third-year crowns to the ground once the bines reach about 2 feet, then retain only a few strong shoots and train them clockwise up the strings. Strip the lower leaves to aid air movement, and cut the bines to the ground after harvest as the plant dies back.
Repotting
Hops are not a container subject, so conventional repotting does not apply. Instead, lift and divide the crowns every few years when the center becomes crowded, shoot vigor declines, or the rhizomes spread beyond their zone.
Size & spacing
In a single season the bines can reach 25 feet (7.5 m) in height and spread 3 to 6 feet (91 to 183 cm) across at the base. Allow each crown generous room and a tall, sturdy support so air moves freely and the rhizomes have room to extend.
When to plant
Hops follow a defined annual cycle driven by the crown's dormancy and regrowth. Plant rhizomes or crowns in early spring once the soil can be worked, train the bines through the long days of summer, and cut the cones in late August and September before the top growth dies back for winter.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Plant rhizomes or crowns in early spring after the soil can be worked
- Harvest: Cones harvested late August through September (late summer to fall)
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Most hop problems present on the foliage, arriving as fungal disease under damp conditions or as pests during summer heat. Early intervention matters because damage that reaches the cones is what erodes the harvest. Match the symptom below, then act while control is still effective.
Yellow patches above, gray-purple sporulation below, and stunted spikes
The angular chlorosis and gray-purple growth point to downy mildew, a systemic pathogen that overwinters in the crown and moves into new shoots as basal spikes, which explains the pale, brittle, downward-curled growth. Because it favors cool, wet conditions and resists eradication once established, remove those spikes and infected foliage before they sporulate. Open the canopy, irrigate at the base to keep the leaves dry, and apply a preventive fungicide through damp spells.
Fix:
- Remove and destroy infected basal spikes and diseased foliage promptly
- Improve air circulation by stripping lower leaves and thinning bines
- Avoid overhead irrigation; water at the base
- Apply a labeled fungicide preventively during cool, wet periods following extension recommendations
White powdery colonies on foliage, shoots, and cones
The white, felt-like colonies mark powdery mildew, a fungus that colonizes leaf surfaces and young growth and, once it reaches the developing cones, deforms and kills the tissue that carries brewing value. Excise the earliest infected growth in spring and train the bines open to sun and moving air, since the fungus struggles where the canopy dries fast. Sulfur or another labeled fungicide holds it back when conditions turn favorable.
Fix:
- Prune to remove early infected tissue in spring
- Improve air movement and sun exposure
- Apply sulfur or another labeled fungicide per extension guidance
Stippling and bronzing with webbing under hot, dry conditions
The fine stippling and bronzing signal twospotted spider mites, which feed on leaf cells and multiply fastest in hot, dry weather, so heat and water stress accelerate a population that then desiccates the foliage. Confirm by tapping a leaf over white paper to see the mites move. A regular strong water spray dislodges them, adequate moisture removes the stress that favors them, and conserving predatory mites keeps the population in balance.
Fix:
- Wash plants regularly with a strong stream of water
- Conserve beneficial predatory mites and other natural enemies
- Provide adequate but not excessive water and nitrogen
- Apply a labeled miticide if populations escalate
Curled, honeydew-coated leaves colonized by soft-bodied insects
The sticky, curled foliage and sooty mold trace back to the hop aphid, a sap feeder that emerges in spring, builds through the season, and secretes the honeydew that the mold grows on. Because the colonies migrate onto the cones and downgrade the harvest, inspect the growing tips weekly and intervene before that migration. Lady beetles and lacewings suppress light infestations, so conserving them does much of the control.
Fix:
- Encourage and conserve natural enemies such as lady beetles and lacewings
- Hose off light infestations with water
- Apply insecticidal soap or a labeled insecticide for heavy early-season or cone infestations
Foliage skeletonized to a lacy vein network in midsummer
Skeletonized leaves reduced to a lace of veins are the signature of the Japanese beetle, whose adults aggregate to feed on the soft interveinal tissue during their midsummer flight. Hand-picking into soapy water in the cool morning, when the beetles are sluggish, removes them at low effort. The damage is cosmetic, so an established bine tolerates the defoliation and continues to yield.
Fix:
- Hand-pick beetles into soapy water in the early morning
- Apply a labeled insecticide during heavy adult flights if needed
Toxicity
Hops pose a serious hazard to dogs rather than a minor one. Both fresh cones and the spent hops discarded after brewing can trigger a sudden, life-threatening rise in body temperature, so every part of the plant and all brewing residue must stay well out of a dog's reach. Cats, horses, and other animals also warrant exclusion, while the cones are the part people use to brew beer.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Moderate
Cats fall within the at-risk group, and although documented cases lag well behind those in dogs, ingestion can elevate body temperature and provoke gastrointestinal upset. Store cones, dried hops, and brewing residue where a cat cannot reach them.
Dogs Severe
This is the clinically dangerous case. In dogs hops can precipitate a malignant hyperthermia crisis marked by heavy panting, a dangerously high fever, tachycardia, agitation, vomiting, and seizures that may prove fatal within hours. Spent brewing hops are a frequent source, sighthounds such as greyhounds carry elevated risk, and any ingestion warrants emergency care.
Horses Moderate
Horses are counted among the susceptible species. An animal that consumes hops may show overt distress alongside a rising body temperature, so exclude the plant and all brewing waste from pasture and feed.
Rabbits Caution
Evidence for rabbits remains inconclusive in either direction, so the defensible course is to treat hops as unsuitable. Withhold cones, foliage, and trimmings entirely.
Livestock Caution
Cattle, goats, and sheep warrant exclusion as a precaution, since the same heat-driven reaction observed in dogs cannot be ruled out. Fence off plantings and dispose of spent hops away from any grazing access.
Birds Caution
The response of birds to hops is poorly characterized, so the conservative measure is to keep cones and dried hops away from them altogether.
People Caution
Adults use hop cones in brewing and steep them into calming teas, and the plant poses low risk to grown-ups. Even so, it is not a food for children, and contact with the bines can raise a skin rash in some individuals.
Keep all hops, including bittered/boiled spent hops from brewing, completely away from dogs. Dispose of used hops securely in a sealed, dog-proof container rather than an open compost or trash that pets can reach.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
Growers generally select hops by brewing character, spanning bright citrus aromas to heavy bittering potential, with one cultivar chosen for ornament instead. The following are the names worth knowing.
Cascade
Cascade is a popular American aroma hop defined by bright citrus and floral notes, which has made it a staple for home and craft brewers alike.
Centennial
Centennial is a dual-purpose cultivar valued for a bold citrus aroma pronounced enough to earn it the name super Cascade.
Chinook
Chinook is a high-alpha bittering hop distinguished by a spicy, piney character.
Nugget
Nugget is a vigorous high-alpha bittering cultivar recognized for its heavy, herbal aroma.
Aureus
Aureus is an ornamental golden hop cultivated mainly for its bright chartreuse foliage rather than for brewing cones.
How to propagate
Hops are propagated almost entirely from the parent plant rather than from seed, which keeps a named female cultivar true to type and shortens the wait to a brewing crop.
DivisionEasy
Early spring while dormant · One growing season to establish; full cone production typically by the second or third year
Division of the perennial crown from an established female plant in early spring, while it remains dormant, is the most reliable method and preserves the clone true to the named cultivar. A division requires one growing season to establish, though full cone production generally waits until the second or third year as the root system matures.
LayeringModerate
Spring through early summer · One season to root before separating
Rhizome cuttings and layered bine sections planted from spring through early summer root readily, taking roughly a season to form roots before separation from the parent. Commercial operations favor clean, disease-free transplants over field rhizomes precisely to exclude mildew inoculum from a new planting.
SeedDemanding
Spring · Two or more years to flower and reveal sex
Seed is seldom appropriate, because seedlings do not reproduce a named cultivar and segregate into male and female individuals. Spring-sown seed needs two years or more to flower and finally express its sex, committing the grower to a long wait for a plant of unknown value.
Myths
Any hop plant will give you cones to brew with.
Hops are dioecious, so the papery cones, or strobiles, that brewers use form only on female plants. Growers retain males solely for breeding and pollination and otherwise remove them, because pollination sets seed and seeded cones are undesirable for most brewing.
Only beer made from hops is dangerous to dogs, not the plant.
The toxic agent resides in the hops themselves, so no beer and no alcohol are needed to cause harm. Fresh cones, dried hops, and particularly the spent hops discarded after brewing can induce a life-threatening febrile reaction in dogs on their own.