|Written by Jonathan Day|
|Wednesday, 23 March 2011 11:27|
It's hops growing time, or at least time to start prepping. I dug through some old emails to put together my list of things that need to be done before they start sprouting. I have Nugget and Tettnanger hops, just beginning the second season. So, if I want a good year, I need to pay attention.
Spring Hop Preparation
I remember fighting aphids last year, so my plan is to spray early and keep an eye on the leaves. The following came from the brew shop where I purchased the rhizomes (Great Fermentations in Indianapolis) when they sent them out.
HOP GROWING INSTRUCTIONS
Plant mixed varieties at least 5 ft. apart. Identical varieties can be as close as 3 ft. if you don't have much room. Hops mainly grow up if they can then lateral sidearms extend off of the main vine. Hops don't have to be grown on an 18' trellis. Some of the less vigorous varieties will yield more if they are limited to more like 10'-15'. Actually, just about anything over 6 feet will work, the vine will just become bushier. The vines are easiest to grow and deal with if they are trained onto strong twine. This twine can be supported by a trellis wire, pole, tree branch or building.
Once the hop is established after the first season, less frequent deep watering is best, preferably drip irrigation. Try not to soak the vine during watering, as that will sometimes encourage diseases. Each spring apply a hearty dose of manure as a top dressing or fertilize with a balanced chemical fertilizer that is recommended for garden vegetables.
DISEASES AND PESTS
Downy Mildew: Pseudoperonospora humuli
The primary disease in hops is downy mildew. By being specific to hops, the disease may or may not be a problem everywhere. The disease first appears in the spring when some of the shoots develop into 'basal spikes'. The spikes are characterized by a stunted form, pale down curled leaves, silvery upper surface and the underside of the leaf turns black. Once the shoot develops into a spike it will not continue to grow and should be removed as it is now a source of infection for other parts of the plant as well as other plants. There must be moisture on the leaves in order for the wind borne spores to germinate. This is why it is a good ideanot to sprinkle irrigate. Lower leaves are also often removed as they create a damp area around the basal spikes ideal for spreading the disease. Downy mildew can be controlled by fungicide such as Kocide 101, but repeated applications may be necessary as rain will wash off the fungicide. Systemic fungicides such as Ridomil and Aliette provide longer protection but may not be available to home gardeners. Hopefully, this disease is not a problem in your area, so don't worry about it unless the spikes appear.
Powdery Mildew: Sphaerotheca humuli
Powdery mildew is the oldest of the fungal diseases affecting hops. Itcaused great damage in the USA when hops were grown on the east coast and was one of the problems that forced the hop industry west where powderymildew does not occur in commercial hop yards. The disease is characterized by white fuzzy mold growing on both sides of the leaves. If the disease proves to be persistent, it can be controlled with sulfur based fungicides.
Hop Aphid: Phorodon humuli
This pest is a problem in all hop growing districts of the Northern Hemisphere except some areas in China. If uncontrolled, this insect is capable of completely destroying a crop. The soft green aphid can completelycover the underside of the leaves, sucking the life out of a plant. They can also appear later during cone formation, particularly in cooler weather, and inhabit the inner part of the cone making control next to impossible at this late phase. Black sooty mold grows on the honeydew of the aphid in hop cones and is often the reason for not picking some vines. The aphid over-winters on various species of Prunus, mainly on sloe (P. spinosa), Damsons (P. insititia) and plums (P. domestica). The eggs are laid in the axils of the buds and hatch wingless females in the spring. They reproduce asexually, and soon produce winged females that migrate to the hop. Once on the hop the migrants produce several generations of wingless, asexual aphids that build up in large numbers throughout the summer unless controlled. The actual aphid has a very soft body and is not hard to kill, but the tallvines and abundant leaves make it difficult to effectively spray the vine and hit all the aphids. Organic insecticides such as insecticidal soap, nicotine and diatomaceous earth work well if effectively applied. Somesuccess can be derived via the introduction of ladybugs and lacewing predator insects as long as the predators decide to stay on the hops. The other option is to spray with a commercial insecticide such as diazinon ormalathion.
Spider Mite: Tetranychus urticae
Spider mites are mainly a problem in hot dry climates. Females over-winter mainly in the soil or under leaves. In the spring they emerge and climb up the vines to feed on the lower sides of the leaves. Very small and just visible to the naked eye, their arrival is more evident by the existence of their fine white webs on the bottom of leaves. Mites are often not as big a problem as aphids, so control may not be necessary. Many of the same insecticides used on aphids are also effective on spider mites. The introduction of predatory mites is also proven to be a somewhat effective control measure.
Please note that most of the above pests and diseases have humuli in the Latin name. This means that they are specific problems on hops and do not infect or inhabit other plants. Therefore, if hops do not have a history of growing near your location, these problems will hopefully not exist in your area. Don't let the potential problems of growing hops stop you anymore than the potential of brewing a bad batch of beer. Mainly, because of the higher heat used in drying commercial hops, the full aromatic potential may be somewhat diminished. Therefore by using lower drying temperatures and hopefully organic growing conditions, homegrown hops arethe best.
In addition to the true roots and aerial vine, the crown also produces underground stems called rhizomes. Rhizomes resemble roots but possess numerous buds and are used for vegetative propagation. Thus propagated, all plants of a given variety are genetically identical.