Kale is no exception when it comes to what veggie plants typically need to grow well. Nutrient-rich, well-drained soil. If your garden is lacking in well-drained, nutrient-rich soil – don’t worry. About two weeks before you plant, be sure to dig the soil about a foot and a half deep. Remove any rocks and break up large clumps. Add a few shovels full of compost and set the plants into the newly well-drained and nutrient-rich soil up to the first set of true seed leaves.
Kale is generally a cool weather crop. It has the highest yields during the early spring and fall. However, it can grow during the summer and the winter – but plan to harvest the kale leaves less often during these months.
If your area experiences winter low temperatures in the twenties, your kale plants should be able to survive the winter with only a layer of mulch. If your winter lows are in the teens, you can either let your kale plants go for the winter, or try to extend the harvest by adding a garden blanket such as Remay.
Kale will continue to produce in lower temperatures with double protection such as a hoop house and row cover or garden blanket.
Since kale plants offer continuous harvests, they generally benefit from regular feedings. If you have a compost pile, you can side dress the plants – which means adding fertilizer off to the side of the main stem. Since kale is a leafy plant, fish emulsion works well as a fertilizer. You can also add compost tea or even a granular fertilizer – about one or two tablespoons per plant every few weeks.
Depending on your type of soil and growing conditions, watering needs will change.
Sandy soils tend to dry out more quickly than loam or clay soils. The best way to determine your watering needs is to stick your finger in the soil and feel for dampness about two inches down. In most cases one inch of rain a week is enough water for kale plants to grow healthy leaves.
During the summer, kale will need more water, particularly if it’s hot and rain is in short supply.
During winter months, it is best to cut down on the amount of water you give your kale plants. Too much water can cause mildew. Plus since the growth is naturally slower during the winter, it will simply need less watering.