Planting Garlic in Fall September 14, 2018 01:35 6 Comments

In late summer or early fall, most gardens are full of delicious vegetables ready for the table and winter storage. This can be one of the most rewarding times for gardeners as the fruits of their labour are fully paying off. As a result, one of the last things on their mind is preparing the garden for planting garlic in the fall.  

Most vegetable growers or gardeners do their garden planning during the winter or very early spring. This means that they often overlook the fact that garlic should ideally be planted in fall. In climates like Canada and the northern United States, fall planting of garlic produces strong flavoured, hardy garlic bulbs that can grow to impressive sizes. With a bit of special attention, garlic can be planted and overwintered in almost any region, including the North.

Three most important steps to planting garlic in the Fall:

Planting Date

The best time to plant garlic in the fall will depend on your location and climate. Your goal is to have the cloves develop as much root growth as possible before winter, without having the garlic emerge from the ground and ending up with green top growth. This means that the date of planting can range from mid-September to as late as the end of November depending on where you live and how long you want your cloves to grow roots before winter.

Generally speaking, it is recommended that garlic in Canada be planted around October 15th every year. This, however, is a very broad recommendation and is not always ideal for every location. 

In colder zone 2 & 3 regions such as Alberta, Saskatchewan, Manitoba, Northern Ontario and parts of BC where winter comes early, garlic planting can start as soon as September 15th and go as late as the end of October (or until the ground freezes).

In warmer regions like southern Ontario, Quebec, coastal B.C or the Maritime provinces, planting can range from early October until the last week of November. If you plant your garlic early in the season and end up with some green top growth above the soil line going into winter, it is not the end of the world. The green leaves may die back over winter, but the cloves will re-grow new leaves in spring.

Planting Depth

Generally, garlic planting depth ranges anywhere from 1" to 3" inches deep. How deep you should plant your garlic cloves will depend on a couple factors.  

The first thing to consider is the type of soil you have. On poorly drained soils like clay, or regions that generally receive very high amounts of rain, planting deeper than 1" or 2" can cause the garlic to decay over winter, in early spring or during wet periods. In sandy or very well-drained soil, planting less than 2" or 3" can lead to drought stress during hot or dry periods.

There are some growers that plant deeper than 3", however, this only works in very dry sandy soils. Generally, any deeper than 3" is considered excessive and will force the garlic plants to use valuable energy when emerging from the soil which can limit the size of the harvested bulbs come fall.

The second factor to consider is the climate of the area. The deeper a garlic clove is planted, the more winter protection it has. In warmer regions like the west coast where winter conditions are mild or in areas with very high snowfall, planting depth is less of a concern. In very cold climates like the prairies or locations that have a lot of freezing/thawing cycles, planting on the deeper side can help protect the cloves over the winter. At at a depth of 2" garlic is usually deep enough to survive the winter, however, 1" can easily have winter kill on the more exposed areas without a thick mulch cover.

Winter Protection

In the colder regions of Canada, covering the garlic with a mulch such as straw, hay or leaves is highly recommended to protect the bulbs over winter. In milder regions like southern Ontario, mulching is not essential, however, can still help protect the garlic from freeze/thaw cycles, as well as keep the soil warmer in order to allow the roots to continue growing into early winter.

Mulching should be delayed until late fall (usually November) when the weather has turned colder. This will help prevent the bulbs from rotting under warm and wet soil conditions. In very wet regions where the winters are mild, mulching is not generally recommended (especially on clay soils).

In spring, remove the mulch covering as soon as possible. The ground will usually still be frozen and the removal will help warm up the soil quickly.