How to Build a Terrarium with Crimson Horticultural Rarities

November 13, 2017


I like to consider myself a budding horticulturalist, although at the moment I only have a small collection of cacti because I don't trust myself to take care of anything else. Luckily our friends at Crimson Horticultural Rarities put together this simple guide for building terrariums and I was there to take photos and follow along. Below are their step-by-step instructions so you can make yours at home. 



  • Plants!
  • Clear glass container
  • Scoop / hand trowel / spoon
  • Paint brush
  • Tweezers
  • Sand / pebbles
  • Activated charcoal
  • Soil
  • Decorative rocks, shells, glass, figurines, moss etc
  • Mister / watering can


Step 1. Choosing a vessel:


    • For terrarium beginners, collect clear glass vessels with large openings, for ease of placing your drainage layers and soil, and most importantly your plants and decorations! As you become more experienced or are looking for a challenge, you can try using vessels with smaller openings, ie: old light bulbs. Get creative; you can find vessels at garage sales, in your grandmother’s attic, or at the store!
    • Wash new & old containers inside & out to remove any residues – you want to create a healthy environment for your new plants to thrive!
    • It’s fun to play with container shapes to compliment and encourage the natural form of your plants, too


Step 2. Choosing your plants:

  • Choose plants with similar light and water requirements. For example, most succulents will want more light and less water. Some houseplants will want more water and bright INDIRECT sunlight.


Step 3. Drainage and soil:

  • Ideally, your soil and drainage will take up no more than 1/3 of the lower level of your vessel. You want to make sure your plants have enough room for their roots, and also foliage to grow.


  • Pebbles/Rocks. Use your scoop or trowel (depending on opening size) to place a layer of pebbles on the bottom of your container, approx. .5-1” thick.


  • Charcoal. Next add a layer of charcoal of about the same thickness. Your sand and charcoal will act as a reservoir for any standing water. The charcoal will improve the quality of your terrarium including reducing bacteria, fungi and odors.


  • Soil. Depending on the size of the plant, and your container, your soil layer should be approx. 2-3” in depth. Check what soil requirements your plants have before planting – succulents require different nutrients than ferns or other houseplants.


Step 4. Planting

  • Still in their plastic containers, arrange your plant(s) as you think you’ll want them to sit in your terrarium. Make slight indentations in the soil to remind you where you want them placed.


  • Gently squeeze the plastic containers to loosen the soil and remove the plants. Shake off as much extra soil as possible. You can rinse the rootball in a bowl of water until the roots are as clean as possible.


  • Dig a hole where you made your indentation using your spoon or finger. You may need to trim some of the root ball back, no more than 1/3 of the length. They will grow back!


  • Place plant, roots first, into the hole and cover roots with soil, pressing firmly down on the soil around the root ball to hold the plant in place. Repeat for all plants.


Step 5. Decorating

  • You’re nearly there! Like icing a cake, adding the finishing touches to your terrarium is where you really get to let your creative vision shine!
  • You can add a layer of pebbles, colorful sand, sea shells/glass, or fun miniature figurines. Moss and lichen covered twigs can be fun additions, too!


Step 6. Watering/Care

  • When you’re finished, use your mister to saturate the soil.
  • The paint brush, or paper towel, is a great tool for cleaning up the sides of the terrarium of any soil or watering over spray.
  • Test the soil before watering. For plants that like moist soil, the top earth should barely feel moist before you add water. For cacti and succulents, touch below the surface layer. Lower soil should be only slightly damp.
  • For a healthy terrarium, encourage air flow by reducing overcrowding. Prune back plants as they continue to grow and any dead foliage. Replace any plants that die back as necessary.


Enjoy! Terrariums make great gifts for every occasion, and are a vibrant addition to your home/office décor!

Crimson Horticultural Rarities is located at 470 49th St, Oakland, Ca 94609. For more information, visit