Once the garlic cloves are in the ground planted and then growing in spring, there are generally four main tasks that need to be taken care of during the growing season. These include weeding, watering, scape removal (if necessary) and scouting.
If possible, it is best to plant garlic in a field that is "clean" and has low levels of weeds. The old abandoned pasture behind Grandpa's barn that hasn't been farmed for the last 20 years might not be the best place to start with. Areas with perennial weeds like thistles or quack grasses should be avoided if possible and planted in future years once these weeds have been removed.
Garlic is an incredibly uncompetitive crop that requires constant and vigilant weeding throughout the growing season. Weed pressure is one of the greatest threats to good bulb size and good yields. Ideally, garlic plants should grow in a completely weed free environment for the entire growing season. Depending on the weed pressure of a particular garden or field, this can mean weeding 6 to 8 times throughout the season. In a particularly weed infested garden or field, weeding may be required at least weekly for the first six to eight weeks and then biweekly for the remainder of the season. In a really clean field, weeding might only be need 3 or 4 times.
When weeding, it is important to be careful not to damage the garlic plant roots as they are relatively shallow growing and can be fragile. Weed removal, while the weeds are still very small, makes weeding much easier and helps keep the depth of soil disturbance shallower. This helps prevent root damage and conserves soil moisture which can be an issue in lighter soils or during dry periods. One of the benefits of having to weed garlic versus other vegetable crops is that it's one of the first crops to emerge in spring, often popping out of the soil even before a single weed has shown up. Because of this, early weeding is easy and helps keep the garlic plants weed free right from the beginning. Always remember, "weed early and weed often" especially with garlic!
On our farm, we hand weed all the garlic and use sharp blade hoes to do most of the work. We have learned over the years that weeding a field many times while the weeds are still very small versus a few times when the weeds are large is far less work! Weeding early and making sure a field is free of perennial weeds is key to our weed management strategy.
Garlic crops like to have a consistent supply of moisture. In general, this means about 1 inch of rain or irrigation per week (up to 2 inches for sandy soils) during the warmer parts of the growing season. It is important not to overwater, as this often leads to disease of the growing plant and poor storage of harvested bulbs. On the other hand, not supplying enough moisture can lead to stressed plants with smaller bulbs (although they will be very flavourful and likely store well). On heavy clay soils, it is best to lean towards watering less with slightly drier conditions whereas on sandy soils it's hard to overwater if the watering is spaced out and managed properly.
Watering should stop about 2 to 3 weeks before the garlic will be harvested, as it helps promote drying of the plants and curing of the bulbs. This is a natural process where the dry conditions help send a signal to the garlic plants for them start the final stages of growth and begin to move towards dormancy.
On our farm, we rely on rainfall and sprinkler irrigation to water our garlic. Being located in the middle of North America and on the edge of both "dry" western Canada and "wet" eastern Canada, we can sometimes have substantial rainfall throughout the summer and sometimes have almost none for the whole season. When watering is needed, we lean on the side of too dry versus too wet due to our heavier soils. We try to irrigate only when conditions are very hot and dry (usually late June and early July) and in spring mostly rely on the moisture stored in the soil from the winter.
When growing hardneck and weakly bolting garlics, scape removal is generally recommended unless you are wanting to let them develop into bulbil capsules. In most cases, scape removal encourages larger bulbs because energy is conserved and diverted to the bulb rather than the flowering structure. Every garlic family and variety responds slightly different to scape removal. Porcelain and Purple Stripe garlics are among the families most greatly affected. Rocamboles tend to be moderately to highly affected, while Asiatics and Turbans have a minor to negligible response.
There is some debate as to what is the best stage of plant growth that scapes should be removed. They can be removed as early as when the structure first shoots up to once the scape has uncoiled, elongated and the capsule begins to swell. Early removal is said to divert the maximum amount of energy to the bulb while late removal is believed to maximize bulb quality and storage ability. Generally, most growers choose somewhere in the middle and remove the scapes once they have formed one or two loops, but before they begin to uncoil and the capsules begin to swell.
Usually, scapes can be snapped off by hand or cut with sharp shears just above the last leaves. You want the cut to dry as quickly as possible in order to prevent a route for infection or diseases. This means it is best to do the removal on a dry day when possible. Scapes are also wonderful to eat and can be cooked by themselves or in any recipes that garlic is called for.
On our farm, we try to do removal sometime between the scapes being fully coiled to somewhat uncoiled. We find that this is the best balance for us when trying to maximize size while not sacrificing storage ability. Scape removal can be a very big job so we try to give ourselves a bit window in case we get bad weather or there are other delays.
Inspecting and observing the garlic plants regularly is a very important job that is often put to the side for other demanding things. Every gardener and farmer knows how many tasks need attention during the growing season and it can be hard to get around to everything quick enough. Scouting, however, is important because it can identify issues or problems that may need to be dealt with before they get out of hand. This usually saves you time in the long run and can even catch things before they truly damage the crop.
Good scouting means a regular walkthrough of all the areas that have garlic growing at least a few times a week, if not every day. While scouting, it's important to be focused on the garlic and not daydreaming about all the other work that still needs to be done. You should be looking for any things that might be affecting the garlic like insects, diseases or even nutrient deficiencies that might show up as yellowing of the leaves or poor growth.
Although garlic does not have as many insect pests compared to other vegetables and is often free of disease if the grower has good practices in place, it is crucial to know that there are still issues that can affect your plants and bulbs. Learning what diseases, insects and nutrient deficiencies affect garlic is always a good thing so that you can know what to look for. Also, it's a very good idea to touch base with any agricultural extension services that your provincial (or state) government might have for vegetable growers. Some provinces have very good extension staff that have a lot of knowledge regarding garlic and other vegetable crops.
On our farm, we try to look at the crop on a daily basis if possible. We have found that problems can literally show up overnight sometimes and noticing it right away is far less stressful than finding out once it's too late.
Next → Harvesting