How to Grow in a Shallow Box
- 1). Select a container for planting. You can choose from a huge variety of commercially available planters and window boxes, or you can use a waterproof container you already have on hand---a plastic storage box, a baking pan, a child's wading pool. Shallow planters especially need to have adequate drainage, in order to prevent mold and root rot. If your container doesn't have drain holes, or enough of them, drill or punch several small ones in the bottom or at the bottom around the sides. Use a drill with a ¼-inch to ½-inch bit or---depending on the material you're piercing---a hammer and nail.
- 2). Line the bottom of the planter with landscape cloth or a piece of screen. This will keep the planting medium from draining out with the water, without taking up space.
- 3). Fill the container with potting mix or "soilless" planting medium that's designed for containers. These mixes often include fertilizer and a wetting agent, or "hydrogel," that holds water. Fill the planter to no less than an inch from the top.
- 4). Plant seeds as directed on the seed packet, or plant seedlings at the same depth they were set in their nursery pots. Consider the size of the mature plants to determine spacing.
- 5). Add a thin layer of mulch after planting, if you wish, to retain moisture. The kind of mulch you choose is dependent on the variety of plant, as well as the growing conditions, and it's a highly subjective decision. If your planter is indoors, mulching probably is not necessary.
- 6). Water gently, until the excess begins to drain from the bottom of the planter. Check the soil frequently for dryness; don't just look at the surface---stick a finger in to feel how moist it is. Shallow boxes don't hold as much water as do deeper containers, and they dry out more quickly. When the weather is hot and dry, you may need to water as often as twice a day.
- 7). Fertilize regularly. Shallow containers have little room for soil nutrients, and frequent watering can wash them out quickly. Apply a balanced, slow-release fertilizer every two weeks (following the directions on the package), or use a dilute liquid fertilizer every other time you water.
- 8). Rotate the planter, if possible, every few days; move it around to follow the sun. This is especially helpful for indoor growing. Outdoors, if your planting box isn't too heavy, you can move it when it needs protection from high wind, excessive heat or violent storms.
- 9). Pinch back your plants, as needed, to keep them compact and productive. Snip off fresh herbs and enjoy them in your cooking. Harvest green onions or baby beets, and plant some more. Pluck the outer leaves of lettuce and allow the inner ones to grow out; the plants will stay small, and your salad bowl will be forever full.
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