Terrariums, a landscape in a jar.
Moss, ferns and stones sealed under glass. An afternoon to build, and then it mostly looks after itself.
What it is like
A closed terrarium is a small water cycle. Moisture rises from the soil, condenses on the glass and runs back down, so a well-balanced jar can go for months without being opened.
Building one is an afternoon of pleasant fiddling. The only real skills are restraint with the watering can and choosing a spot with light but no direct sun.
Indoors · Solo, For two, With kids
Is it for you?
You will probably love it if
- You want plants but forget to water them
- You like arranging small scenes
- You have a bright spot out of direct sun
Maybe not, if
- Your only free shelf gets hot afternoon sun
- You want a hobby that keeps you busy every week
- You would rather grow something you can eat
The starter kit - $52
- A large glass jar with a lidAny clean jar with a wide mouth works; a new one is about $10Free
- Small gravel or clay pebblesA drainage layer so roots do not sit in water$9
- Horticultural charcoalA thin layer that keeps a sealed jar fresh$10
- Potting mix, small bagPeat-free houseplant mix$8
- Moss and two small plantsFittonia, small ferns and cushion moss like closed jars$25
- Everything you need to beginAbout $2 a month after that$52
Typical US prices for entry-level gear, rounded. Last checked October 2026. How we get the numbers
Your first project: a closed moss jar
Two fingers of gravel, a dusting of charcoal, then three fingers of damp potting mix.
Tallest plant at the back, firm the roots in with a spoon handle.
Press moss onto bare soil and set one or two stones for scale.
A few spoonfuls of water, wipe the glass and put the lid on. Open it for a day if the glass stays fogged.
Why people quit
- Mold in the first monthToo wet. Leave the lid off for a few days and remove anything fuzzy.
- Cooked plantsDirect sun through glass overheats a jar within hours. Bright shade only.
- Succulents in a sealed jarThey rot in humidity. Closed jars are for moss and ferns.
How it compares
| Terrariums | Succulents and cacti | Bonsai | Dried flower wreaths | |
|---|---|---|---|---|
| Start cost | $52 | $37 | $76 | $45 |
| Each month | $2 | $4 | $8 | $10 |
| Space | A shelf | A windowsill | A balcony or yard | A table |
| Noise | Quiet | Quiet | Quiet | Quiet |
| First result | 1 afternoon | Same day | 1 growing season | 1 afternoon |
| Mess | A little soil | A little soil | Soil and clippings | Dropped petals |