I recently joined a group of fellow design writers at West Elm for a planting and terrarium-making workshop led by designer Shane Powers, best known for his work as the style and decorating editor for Blueprint and Martha Stewart Living. Powers, who has developed products for brands such as Martha by Mail, collaborated with West Elm to create a collection of garden-vessel designs featuring his love for simple, organic forms.

Woodland-style terrariums are everywhere, so it was refreshing to see how Powers used succulents, cacti and sand to make terrariums and other plantings with an unexpected twist. These design tips from his workshop will get you started creating unusual indoor gardens of your own. West Elm Powers began by adding maidenhair ferns to one of the ceramic vessels from his West Elm collection. First he added a base of soil, then a layer of activated charcoal (the same material used in aquariums). Then he nestled the ferns into the soil. West Elm Shane Powers Ceramic Wall Planters - $19 To plant an orchid in a ceramic vessel, use orchid mix (a mix of tree bark and charcoal). The roots should be green — remove any white or yellow ones. Orchids should be watered every 12 to 14 days.

Powers' design tip for orchids: Remove the plastic ties that often come with orchids and replace them with twine.

Powers gave these ceramic containers a round, soft form — rather than an angular shape — since they're designed to stick out from a wall. West Elm Powers also demonstrated how to create a terrarium in a fishbowl with succulents and different colors of sand:

1. Add a layer of gray sand (available at flower markets) to the bottom of the container.

2. Nestle succulents and cacti in the sand. You can leave them in their containers if you like.

3. Add a layer of smooth black stones.

4. Top with a layer of brick-color sand.

5. Clean sand off the leaves with a soft paintbrush. West Elm To make a terrarium in this glass vessel, Powers started with an inch of gravel. Then he added a thin layer of charcoal and a few succulents (this time removing the plastic pots and loosening the roots) inside the terrarium. He added dirt around the plants using a wooded spoon, to protect the glass and his hands. West Elm This fishbowl from the collection holds a delicate fern in a small pot.

Care tip: Avoid overwatering or pouring water directly on terrarium plants. Water ferns in a fishbowl vessel every 7 to 10 days, using a turkey baster or dropper to avoid spills. Check the moisture level of the soil by sticking your finger in the sand.

For succulents in a glass terrarium, Powers suggests waiting a month between waterings. West Elm Air plants don't need dirt, so they can float anywhere in dirt-free glass vessels. Powers designed these handblown containers to allow air circulation for the plants. West Elm To water air plants, simply soak them in a bowl of water.