I’ve had a request for plant combinations for window boxes. I love window boxes. I have several and I am contemplating more.There are lots of books and articles on window boxes but I thought I would give you some of my preferences and opinions. I have also posted these and some additional images and links on Pinterest (which I am addicted to now).
Getting Started:
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Self-Watering from Gardener's Supply, $29+
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Self-Watering Insert, Gardener's Supply $16+
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Hydromat, Gardener's Supply $9.95+
1. Picking a pot:
For a sunny location you will need either a self-watering box/pot (it has an extra reservoir of water below to help keep the plants roots moist) or a kit to add a reservoir to the bottom. Alternately you could add a hydromat to the bottom of an existing pot.
If you are growing to grow some of the larger veggies or house plants I recommend getting one that it a little deeper.
I have several self-watering ones that I love from Gardener’s Supply.
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Potting Soil w/ Water Crystals
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Vermont Company Fertilizer
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Organic Slow Release Fertilizer
2. The Soil:
You will need sterile potting soil. Potting soil is lighter than regular soil. I also strongly recommend the soil that has crystals to store water. You can also buy soil that has some fertilizer already in it.
3. Fertilize:
I have to admit that I am totally lazy about fertilizing, but for these kind of conditions the plants could really use it. You can use the slow release dry kind or a liquid fertilizer. There are a lot to choose from. If possible look for an organic one such as one from Vermont Compost (which I have used).
4. Picking a Location:
For most vegetables and herbs you will need at sun to part sun. For shadier locations there are a lot of house plants that will do well, but not as many veggies.
Plant Types:
The typical plant recommendation for window boxes and planters are to use 3 types of plants: low vines for the the front, bushier middle plants and tall back ground plants.
Lately I have been looking for alternatives to the traditional annual selections. I am particularly interested in combining perennials with edibles and houseplants. Perennials cut down on the cost of buying annuals every year (plus they typically look good into the winter) and I am always looking for a spot to grow some fruit and vegetables. I also have a number of house plants that I like to get outside in the warm weather. Below are some suggestions. Do you have any recommendations?
Also here is an interesting and helpful article on edible window boxes.
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Nasturtium (Jewel of Africa), Parks Seed
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Strawberry (Tristan), Strawberry Seed Store
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Sweet Potato Vine (non-edible)
1. Front of Window Box/ Planter: Low Vines & Trailers
Traditional Annuals include: sweet potato vine (available in lime green, red, and purple), variegated ivy, variegated vinca, petunias (trailing kind), Cotoneaster, Solanum laxu, Golden Moneywort, Silver Falls Dichondra
House Plant Alternates:Ivy, hen and checks (not trailers but pretty)
Edible Alternates: Nasturtium, strawberries, peas (pea tendrils are tasty in salads)
Perennials: Ivy, vinca, lamium (I grow this in my part shade flower boxes)
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Lettuce, Parks Seed
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Mustard (Red Giant), Parks Seed
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Mizuna, Parks Seed
2. Middle of the Planter: Bushier medium height plants
Annual examples include: coleus (my favorite) petunias, pansies (in fall and spring), Geraniums
House Plant Alternates: Jade Tree
Edible Alternates: Red and Green Leaf Lettuces, Frisee, Basil, Oregano, Mint, Rosemary, Spinach, Redux (part shade), Curly Parsley
Perennials: Hosta (shade), sedge (shade), heuchera (part shade)
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Chives, Parks Seed
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Swiss Chard, Park Seed
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Bromeliad
3.Back of the Planter: Tall background plants
Annual examples include: cordylines, Colocasia
House Plant Alternates: aloe plants, spider plants, snake plant (Sansevieria), Bromeliads
Edible Alternates: Chives, Scallions, Swiss Chard, Small Pepper Plant (i.e. habaneros)