Having plants indoors is a wonderful way to experience life around you through winter. 

Developing a green thumb for potted plants took me longer than learning any other concept in gardening, but finally, it clicked. Here are a few tricks I figured out along the way.

Soil health

With houseplants, you’re zooming in on one living thing and creating an environment in which it can thrive separate from any larger ecosystem. My journey to becoming someone who can keep a potted plant alive began with recognizing and accepting this concept. I’d always crinkled my nose against fertilizers, wanting to opt for the “natural” path. But potted plants are not in a natural environment. They’re isolated.

Because of this reality, adding nutrients is key. I’ve liked using “Kelp Help” and “Mary’s Alpaca Poop” as a microbial food source and plant fertilizer.

Additionally, I recommend repotting every year. I like to refresh the soil in my potted plants each year in late summer. It’s a great time to clean up a plant’s roots, add fresh potting soil (natural and organic, with slow-releasing fertilizer), and give it a thorough watering. A little fresh soil goes a long way.

Pots, water & airflow

I’ve never been someone who keeps to a watering schedule. For me, watering potted plants is like an ongoing dialogue. Observation has been key in this area of house plant parenting.

• Terracotta, cement, enameled, glass, cardboard or plastic? The type of pot that houses a plant makes a huge difference in how it grows. Every container affects water differently, which dictates the environment for the soil and roots.

» Choose terracotta or cement for plants that like to drink a lot of water, since these materials are more breathable. 

» Enameled (glazed) pots hold water in more and keep the soil moist, so be sure plants in these pots are happy with “wet feet.” 

» Glass containers are great for carnivorous plants, since they won’t add any nutrients to the soil like terracotta pots will. 

» I’ve had great success keeping my aloe plants in cardboard pots without saucers underneath, which keeps me from overwatering them.

» Plastic will always leach, so save it for non-edible houseplants.

• Don’t forget air flow. Both plants and humans do better with a little fresh air. Breeze is an easy thing to forget about inside, but plants are much happier with a little air rustling their leaves, which promotes water evaporation and transpiration, makes their limbs grow stronger, and prevents condensation on leaf surfaces. Air flow also helps keep soils healthier and reduces the growth of fungal infections.

• Break through the surface. Watering doesn’t just carry water down to a plant’s roots; it also pulls oxygen down, too. That’s part of why an occasional, more vigorous watering will help keep a plant strong, rather than only ever gently adding water. Potted plants tend to form a layer on the surface of their potting soil, which blocks air flow and oxygenated water from getting down into its roots. Break up this layer of soil with your fingers and you’ll notice instantly how much happier a plant looks.

What about worms?

A fun way to create a garden ecosystem inside is by adding composting worms to a windowsill planter box. I’ve had luck with a non-sealed wood planter box that’s half plants, half worm bin. The plant gets to enjoy the worms wiggling through the soil, leaving nutrients and pockets of air in their tracks. And I like to think the worms enjoy navigating through the plants’ roots.

The idea behind worm composting is that waste is something that doesn’t exist in nature. We created it.

Mary Appelhof was a torchbearer of ecological awareness and a full-hearted lover of worms. Her brief and insightful book, “Worms Eat My Garbage,” is an approachable guide to maintaining a home vermicomposting system—turning food scraps into rich organic matter using worms. It’s a quick read, and interesting enough even for those not sold on housing worms (though she’s very convincing!). By exploring the process of worm composting, Appelhof invites us to appreciate the fantastic abilities of some of nature’s smallest creatures, and the beauty of life itself.

I don’t think I’ll ever be done experimenting with how to bring nature indoors in interesting ways. The resourcefulness that comes from manipulating an indoor environment to make a plant happy is a fun challenge that teaches me more about how nature works in the subtlest of ways.