So, you want to grow great garlic in Wisconsin? Anyone can grow garlic - growing great garlic is a true challenge!
Here's what to do:
The biggest factor for garlic is not seed, sun, or water - it is SOIL. If you do not grow garlic in the right soil, garlic will not grow well no matter what you do. That means small bulbs and lots of wasted time and most importantly a huge psychological let-down. Remember to till your land and rake to remove rocks and weeds.
The best soil for garlic is well drained loam. Sandy loam will also work, but will require more watering in dry times. Till in some chicken manure in the fall (at least one month before planting if using chicken manure - seriously, no less than one month) and unless you have soil that is completely played out, you are ready to go!
Sun also plays an important role, but not as much as with leafy plants or trees. Make sure your garlic is planted in full sun and gets at least 6 hours sun every day.
Watering in Wisconsin is rarely necessary and, if it is, is usually the month before harvest (mid-May-mid-June). Two weeks before harvest (around July 1st in Southern Wisconsin) watering should be stopped so soil dries and you don't pick "mud-balls" with garlic centers.
Seed is also a critical factor for garlic. Garlic takes time to acclimate to it's conditions - planting large cloves/bulbs the very first season is not advisable because there is a very good chance the garlic is acclimated to the seed providers criteria and that will cause severe loss or small crops. Seed shouldn't be tiny, but average size cloves are what to plant the first year. Then save cloves as they get bigger (a sign of acclimating) each season to get slightly larger bulbs the next season. After several seasons, your garlic will be "peak-size" for the variety selected.
There is one more very critical factor with garlic: Planting Window.
The planting window in Southern Wisconsin is around Mid-October and only lasts about 7 days. It is imperative that garlic is planted roughly 2 weeks before the first hard frost. This is difficult to predict at times in Wisconsin! Ideally, you want your cloves to be in the ground and starting to root BEFORE the frost comes - if they are put in too late, they will be lost over winter. If they are put in too early it is okay as long as growth before first hard frost is minimal (no more than a few inches).
Garlic should be planted in rows at least 16" apart that run North/South. Space between bulbs should be 6-8 inches. Plant cloves at a depth of 4" - do this exactly and measure or there is a good chance your cloves will either pop out of the ground with frost-heaves over winter, or they will be too deep and not have the energy in the clove to actually get to the surface in the spring (especially in years where it goes through numerous freeze/thaw cycles).
Cover planting with straw when completed.
In spring, some remove the straw - that is a function of how much water your soil holds in our experience. If you have wet soil regularly, remove the straw and water when necessary. If you have soil that will dry out and is very well drained, leave the straw and water if necessary. Finally, weed when necessary. Your field does not have to be pristine to produce good garlic, but garlic is a poor competitor so do not let weeds get the upper hand. The straw helps, and we generally do 2-4 weedings per season. Garlic comes up around March, so that is not much weeding over a 3 month+ period.
Best of luck to all growers! Thanks again for choosing Wisconsin Garlic!
Click here for a PDF copy of How to Grow Garlic.
So, you are finally ready to harvest your garlic. It's not difficult at all, but there are a couple things to keep in mind:
1.) Timing - if you harvest early, your bulbs will not be "filled-out." If you harvest late, your bulbs will be "popping" out of the skins and/or growing cloves outside the bulb.
2.) Watering - don't water for about 2 weeks before your planned harvest. This will prevent mud from clinging to your bulbs which will make harvest a generally miserable experience.
3.) Pulling - never pull bulbs like weeds. Instead, use a small shovel and loosen the dirt around the bulb. Then pull the bulb out and remove loose dirt from bulb/roots. Leaving some dirt on is not detrimental and it will come off easily when cured.
4.) Curing - once your bulbs are pulled from the ground, it is time to cure. We generally hang our bulbs in bunches of 25 with baler-twine or something similar. Bulbs must be left in a cool dry place for 4-6 weeks while also remaining out of the sun. Label each bunch with a sticky note wrapped around one or two stalks per bunch - it will hold if the entire glue-strip is folded over and stuck to the other side.
5.) Post-Curing - Finally, you are ready to market or eat your bulbs. If marketing, you still have some work to do: use a soft brush and remove any remaining dirt from bulb and roots. Then use a hand-trimmer/cutter to remove the roots and stem. Roots can be shaved down close to the bulb - the stem can be cut back to about 1" or more. Longer stems will help garlic retain moisture and remain "good" longer. Do not use normal scissors - they will break.
Non-irrigated Hardneck -
Plant 1 lb:
Yield 4-6 lbs: Average Yield
Yield 6-8 lbs: Above Average Yield
Yield 8-10 lbs: Certified Garlic Master
Yield 10 lbs+: Liar!
Non-irrigated Softneck -
Plant 1 lb:
Yield 6-8 lbs: Average Yield
Yield 8-10 lbs: Above Average Yield
Yield 10-12 lbs: Certified Garlic Master
Yield 12 lbs.+: Liar!
Insect predators in Wisconsin are rare. We have heard stories of locusts in the southern US coming through and decimating acres in one day, but even in the south that seems to be a rarity. In Wisconsin Thrips are the biggest insect problem; they rasp the plants to use as a food source. This appears as silver streaks or white blotches on leaves. Bulbs will be undersized with severe infestations that are not controlled. If Thrips are a problem in your field, we suggest using a soap spray to control. Use real soap (like Dr. Bronners or Fels Naptha) and mix about 2 tablespoons per gallon of water. Use this several times to allow soap spray to permeate down into leaf-folds where thrips hide.
Nematodes are another problem in Wisconsin. These are very small worm-like creatures that live in the soil. Nematodes live inside the garlic plant and will eat the leaves, stem and bulb from the inside out. Often, nematodes will not significantly damage garlic bulbs, but there will be tissue destruction and coloration changes that limit bulb quality. Nematodes can lie dormant in soil for years. Nematodes build up over time and once at a critical level, can wipe out an entire crop. Rotate your crops on at least a 4 year cycle (8 is better and for garlic, any longer time is preferred due to nematodes and viruses).
Leafhoppers don't just destroy plants by rasping, they are also virus carriers. If garlic is the first thing up, that's what they eat. We came across this information recently. It was news to us at the time, even though this information is a couple of years old. We had the same winter here that they had that season - very mild, with the little snow there was melting early and things coming up VERY early. We did not have leafhopper/virus problems of any kind that season. Unfortunately, it wiped out the entire Minnesota specialty crop that particular season according to this individual who lost 10,000 plants! For home growers, you could cover plants with straw and make sure they stay covered. For commercial growers, there is no solution we know of for a scaled-up operation.
On 8/14/12, A Minnesota Grower Wrote:
The Minnesota boutique garlic industry was devastated this year by a disease that has been identified as "Aster yellows". It is a phytoplasma that is carried by leafhoppers, and is introduced into a plant when the leafhopper feeds. Garlic plants are normally not affected because the leafhoppers generally prefer other types of plants. Because of the mild winter the garlic sprouted earlier than usual, and the leafhoppers migrated earlier than usual. There was little else to feed on at the time of their arrival so the leafhoppers fed on the garlic and infected it with the Aster yellows disease.
The disease crippled or destroyed most of the garlic crops here. This is apparently a native disease, not an introduced one, that exploded this year due in large part to the extraordinarily mild winter of 2011-2012. Most of the commercial boutique garlic growers in Minnesota lost everything, including what would have been used for seed stock, so they will now be starting over from scratch. Most likely some growers will quit the business entirely.
I had been expanding my crop over the last five years with the intention of going into the garlic business myself. I too lost everything - 10,000 plants - which included my seed stock for next year."
Yikes! Everyone out there trying to grow needs to be aware of what can happen with pests after mild winters AND the double-whammy of the disease they might carry too.
Leafhoppers can also carry Aster Yellows. Wikipedia has an informational page available:
Fugal diseases and viruses are a huge concern.
White Rot is a big threat to commercial production and comes from the soil where it can lie dormant for 20-40 years. Small growers usually will only have a few plants that can be identified and pulled long before it's a problem. White Rot is easy to identify as the leaves will yellow and partially wilt and die. It usually occurs in little groups or on single plants in fields that are mildly infected. Remove any plants that exhibit these symptoms around mid-growing season (around mid-May in Wisconsin) and check for a white, web-like, "organic-netting" around the bulb/soil and remove as much as possible, along with the bulb and dispose.
Viruses are a huge concern for garlic in the Western U.S. right now. Mosaic virus and yellow dwarf virus are two of the most common. From what we have read, and at this point in time, all garlic carries viruses and some exhibit symptoms. Mosaic virus will show as yellow spots on leaves that resemble a mosaic pattern. This virus will usually not exhibit anything more than the yellow spotting in from our experience. If there are some plants affected severely, they can be identified and removed easily and fairly early in the season.
Yellow dwarf virus was first identified in the State of Washington in 2005 from what we have read. It was in California before that and these two states represented (and continue to represent) almost all commercial garlic grown in the U.S. That is only 10% of what is used - 90% comes from China... We all need to think about that; there are things to trade for and things to produce domestically. Food might be something we should manage ourselves!
Further information about garlic viruses may be found here:
Characterization of viruses associated with garlic plants propagated from different reproductive tissues from Italy and other geographic regions - Phytopathologia Mediterranea (January 2012, DOI:10.14601/Phytopathol_Mediterr-10479)
Clicking the link above will open a new window and take you to the ResearchGate.net website. Click on the PDF link under "Full Text" to read the report.