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Designing with Plants
If you're unsure how to combine plants attractively, follow this easy formula from the late Kathy Pufahl, horticulturist and owner of Beds and Borders nursery. Pufahl suggests picking one type of plant that grows up like grasses, spiky plants, geraniums, or other flowers on long, straight stems; one that trails down like ivy, sweet potato vine, thyme, lobelia; and one bushy type to fill in the middle like impatiens, petunia, dwarf ornamental pepper. Like other types of container gardening, if you have room, you can add a fourth type as filler, one that contrasts in color, texture, or foliage size with the others in the box.
Planting the Window Box
The best Soil Recipe For Window Boxes is usually a mix of peat or coir, perlite, and vermiculite. Provide some nutrients and help retain moisture by adding screened compost—it can be up to 20 percent of the mix. Moisten with warm water before planting and set the plants into the mix to the same depth they were in their containers. Firm them in and water again. Allow about an inch of space between the soil and the top of the box.
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Keep Them Looking Good
Knowing How And When To Water your plants is essential for cultivating a healthy window box. If it sits in direct sun for much of the day, you may need to water both morning and evening. Water until it runs out of the drainage holes and don't assume that because it has rained that your plants have enough moisture. If your plants droop in the sunlight but recover in the shade or after sundown, they need more water.
Try not to let the soil completely dry out, especially if you use a soilless peat-based mix. Once peat dries, it no longer absorbs water but actually repels it, becoming almost impossible to rewet. If the peat does dry out, try this remedy from John Begeman, agriculture and natural resources agent at the University of Arizona: Add a few drops of liquid dishwashing detergent to a quart of water and then water slowly with this solution. The soap breaks the barrier to the soil and allows the water to be absorbed. The results should last a long time, so you shouldn't need to use the soap solution more than once or twice in a season.
Mulching the soil in a window box helps hold moisture in and gives a finished look to the box. Whatever you use—cocoa shells, finely shredded bark, or moss—be sure to thoroughly water the plants before adding the mulch or it could act as a barrier to the water. Periodically check to be sure that water is getting through to the soil and isn't running off the top of the mulch.
Soil mixes don't provide enough nutrients for the plants to thrive the entire season, and whatever nutrients there are can wash out of the drainage holes when you water your plants. So to keep your plants healthy and growing, use organic fertilizer every two weeks.
Dead and decaying flowers, stems, and leaves can be sources of fungal growth, so be sure to pinch them off when you see them. Regular deadheading keeps annuals flowering instead of going to seed, and keeps plants looking their best.
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Great Window Box Plants
Black Mondo grass
Golden creeping Jenny
Sweet potato vine
Trailing coleus varieties