How to Build an Indoor Window Garden

If planting herbs, pick around five varieties that you use regularly for cooking. Basil, oregano, chives, thyme, mint, and rosemary are good choices with which to start. Each has its particular needs, but all of these are hardy and well-suited for window life.

There are three ways to start your herb garden; you can start from seeds; with cuttings from store-bought plants; or from transplanting your own garden-grown herbs.

For those who like to get their hands dirty, try starting herbs from seeds. It's the least expensive way to grow an indoor herb garden, but it does take some patience and special attention to your plants.

Helpful Tip

When purchasing seeds, make sure you choose compact varieties. The regular varieties are meant for growing in large spaces and can be difficult to grow indoors.

Use small pots around 6" in diameter. Terra cotta or heavy clay pots work best, but any pot with good drainage will do. Fill each pot with potting soil, and, following the directions on the packets, add the seeds to the depth specified by the manufacturer. Mist the soil with water, keeping the soil damp but avoid over-watering. You may have to mist the herbs every day, especially if your home is especially dry during the winter months.

Stem cuttings are another easy method to grow herbs indoors. Before the growing season ends, start your indoor herb garden with some cuttings from your outdoor plants if you have them or use cut herbs available from retail stores. Cut about six inches of a stem at the base of the plant. Once the branch is cut, strip the foliage off the bottom so it won't rot. A root should develop anywhere a leaf or stem has grown. Place the cutting in a small jar of water so it can set roots. Keep in mind that these cuttings need a sunny location, and the water should be changed out every day. Once the cutting has sprouted roots, you'll need to plant it in a pot. Fill the pot with potting soil and plant the cutting.

Helpful Tips

To keep your herbs growing, use them! Snipping off enough leaves for a recipe or garnish will keep the plants healthy and thriving.

Consider placing your pots inside a window planter when you're finished planting for a consistent look to your garden.

Start planting. If planting flowers, petunias and pansies are good species with which to begin your garden. Some vegetable varieties, such as tomatoes, can work in an indoor garden, but often require supplemental light and/or heat sources, such as lamps or grow lights. Take the plant out of the pot it was in when you bought it and gently shake off the old potting soil from the root ball. If the roots are tightly wound, gently slice the sides of the root ball in two or three places.

Fill 1/3 of a new pot with potting soil and insert the plant stem or root ball. Fill in around the sides of the root ball with more potting soil, pressing lightly. The plant should be at the same soil level as it was originally and there should be a 1/2'' to 1'' space from the top of the mix to the lip of the pot.

Helpful Tip

When selecting potting soil, choose a mix that specifically identifies what it's made of. Avoid bags that just say "peat" or "compost." Instead, look for potting soil with specific ingredients, like "sphagnum peat moss." This potting soil will be higher quality and better for your plant.

When you're done potting your plants, organize the pots on the sill or group a few pots together inside a planter and place it on the sill.

Water the plant, thoroughly soaking the potting mix. Then allow it to drain. To ensure that your plants grow healthy and strong, feed them immediately after repotting and on a regular basis. Be careful not to use too much fertilizer; follow package instructions carefully. Use a liquid plant food such as Miracle-Gro® Liquid All-Purpose Plant Food, available at your local True Value hardware store. Use sharp scissors to cut away browned and dead stems and tips.

You'll get the best results by making your indoor window planter as wide as the outside dimension of the window casing and no wider than the interior windowsill. The planter should be at least deep enough and high enough to accommodate a 6" diameter flowerpot. We suggest that you use 1'' x 8'' lumber for the ends and faces and 1'' x 6'' lumber for the bottom, at a minimum.

Cut the pieces for the front, back and ends from your good lumber. You can use a lesser-grade lumber, such as No. 2 pine, for the bottom. Use a circular saw or table saw when cutting the pieces for your planter.

For the front and back, cut or plane a 5-degree bevel along the bottom edge of each piece.

To make the ends, cut (with the grain) two pieces of 1'' x 8'' lumber to be 6'' wide. This will correspond to the height of the end. Then cut the sides of those pieces at an 85-degree angle to create a 5'' and a 7'' base on these two trapezoidal pieces.

To create the bottom, set the saw's bevel adjustment to 5 degrees, and cut (with the grain), the piece of 1'' x 6'' lumber so that it is 5'' wide. Use a plane to bevel a 5-degree angle on the two lengthwise edges. Next, cut the bottom piece 3/4'' shorter than the length of the front and back pieces so it will be recessed 3/8'' and fit properly with the front and back when assembled.

Use a rubber sanding block or finishing sander and sand all the pieces smooth. Start with coarse sandpaper, such as an 80-grit paper, then use a finer 120-grit and finish with 220-grit paper. The coarse paper removes rough edges and splinters, while the fine paper prepares the wood for finish. Always sand along the length of the boards with the grain, not against it.

Now, put your planter together. Using a small brush with a 1/2'' tip, apply waterproof wood glue on all edges of the bottom and rest it on 1/2'' thick spacers. Clamp the two ends onto the bottom and pre-drill 3/32'' pilot holes for the fasteners. Secure the ends to the bottom with 6d galvanized nails.

Glue the front and back edges of the end pieces; similarly clamp and attach the faces to the bottom and the ends. Wipe off excess glue with a damp cloth and touch up with your sander as needed.

Helpful Tip

Pre-drilling prevents the fasteners from splitting the wood (especially hardwoods) and makes it a lot easier to accurately drive the nails or finishing screws.

Make your planter waterproof using a synthetic rubber coating. Mask the top edges of the planter with masking tape and apply the coating to the interior surfaces. Synthetic rubber coating is available in spray cans or as a brush-on liquid. It will form a flexible, waterproof surface when it dries.

When the interior surface dries, reposition the masking tape over the top inside edge and finish the sides and top with any interior paint, stain or polyurethane finish.

Once you've put the planter together, it's time to put it in place. To mount the planter on shelf brackets or on a shelf supported by brackets, you'll have to install those brackets into solid wall framing with screws. If you mount the planter to the brackets, glue 1/2'' wood spacers to the bottom at the bracket locations.

If you plan to place soil directly into your planter, don't forget to provide drainage. Put at least 1-1/2'' of crushed stone in the bottom of the planter, covering it with a layer of landscape fabric before you add soil and plants. If you prefer to keep plants in their pots, simply put the pots in the planter and fill around them with sphagnum moss, pine bark or similar mulch.

Helpful Tip

Set smaller pots on blocks of wood or on some mulch so their tops will be even with those of larger pots.

Great job! That’s all it takes to get started on an indoor window garden.