Collard greens are a staple garden vegetable that are just as easy to grow in containers as they are to grow in a traditional in-ground garden. These nutritious greens can be grown year around indoors as long as you have a large container and a sunny location. Grow your own collard greens in containers (indoors or outdoors) with these planting tips.
Select a container that is at least one foot deep and two feet wide. Collards have relatively shallow roots, but the plant produces large leaves and will need space to grow. Make sure container has several bottom drainage holes and place a coffee filter or two in the bottom of the container before adding potting soil to prevent the soil from leaching out during watering. Fill container with good quality potting soil. Place containers in a sunny location. The more sun the plants receive, the better.
Plant seeds or bedding plants 2-3 feet apart in very large containers, or one plant per container. Sow seeds thickly in rows that are 2 feet apart, thin out the seedlings after they sprout. When growing collard greens indoors, sow seeds every two weeks for a continual harvest. When containers are located outdoors, plant a crop of collard greens in early spring, then another crop in late summer for a fall harvest.
Collard greens like to be fed and steady diet of high nitrogen fertilizer and water. Nitrogen promotes leaf growth and with collard greens, that’s what you want. Choose an all-purpose fertilize with the first number (nitrogen) being the highest. A 10-2-8 water soluble fertilizer feeds and waters the greens at the same time and will give you more than one harvest off each plant.
When the leaves are the desired size, use a sharp knife to cut off the entire plant to about four inches above soil level. Immediately feed and water the plant and it will begin growing a new set of leaves. Individual leaves can be harvested from the plants at any stage of growth. To harvest individual leaves, just pop or snip them off near plant base. If containers are located outdoors, a light frost in early fall will not harm the plants, quite the opposite in fact. A light frost will give the collard greens a sweet flavor.