Planting In Glass Containers

Here are 3 great ways to be creative when planting in glass containers – namely glass planters, terrariums, and cutting displays.

Planting in glass containers has become more popular in the last few years. This shows in the number of glass designs now available for planting. There is however a caution before even beginning to embrace this trend. Because there are no drainage holes in glass; the soil medium, care and plant choice are critical.

Here are 3 great ways to use glass when planting in containers:

• As an open planter, with careful choice of soil substrate and plant type.Very specific care is needed to avoid drowning plant roots.
• As a closed system with a specific plant choice that will be able to handle the conditions in a closed eco system.
• As a display for root cuttings. This last one is becoming more and more popular. Propagate your houseplants in water and display them at the same time.

Glass Planters

Open glass jars, fish bowls etc need the addition of a thick drainage layer of gravel or pebbles. This must be at least 2cm thick. Excess water will be able to sit in this layer. The substrate layer will able to pull the water upwards by capillary action as it dries. The roots of the plants shouldn’t be able to get to this layer to avoid root rot.

The substrate or planting material layer goes in next. It can be just a layer of potting soil. But if using succulents, a mix of 50% silica sand to 50% potting soil is better for extra drainage. This layer needs to be at least 10cm thick.

TIP: Add a piece of landscape fabric between the gravel and the substrate to keep the layers separated. Plant the plants in the substrate and fill in around with a decorative layer of pebbles, bark or coloured glass. Choose plants that have different colours and textures if making mini gardens.

Care and maintenance:
Position in a spot with indirect light, but make sure the plants chosen get enough light for their species. This must be without direct sunlight, which will cause algae to grow. Water once a week with a little water. Make sure the water drains into the bottom gravel layer and the planter doesn’t become waterlogged. These pots will need less watering than regular containers that drain through drainage holes in the base.

READ MORE: More DIY – a wall of pots!


Closed systems need special treatment. Use a selection of plants that like humid wet conditions like ferns, mini palms, peperomias and carnivores. Terrariums can be big or small, from a small glass jar to an old fish tank. There are so many ideas to create perfect mini gardens, so this type of gardening is quite addictive.

To make a closed system terrarium you will need a glass container with a lid, or some way to close it off to create a mini eco system. Add a 2cm thick layer of gravel on the bottom. There are long handled terrarium tools available. These will make it easy to create your designs and level out the layers through small bottle necks. Add a 1cm layer of activated charcoal. This will keep the water in the glass from turning green and keeps the air fresh.

For the planting substrate layer, use 50% palm peat to 50% seedling mix well blended. Make this layer at least 5cm or more. Add a piece of landscape fabric between the layers to prevent them mixing. Make small holes in the substrate and plant small plants into the container firming down into the soil. Choose plants for different coloured and textured foliage. Bits of driftwood or ceramic forms for interest and add a small groundcover or moss to finish it off.

Once everything has been planted and all the decorative bits are in place, water down the sides of the glass. Turn the bowl as you go. For the first week, leave the terrarium open to allow the condensation to escape. For the second week close the opening halfway. Once there is no more condensation you can close the container fully.

Care and maintenance:
Place in a well-lit area out of direct sunlight. Once the system inside the glass is stable, there is very little need for any watering. But there may be a need to clean the glass, prune plants and remove debris.

Cutting Displays

A selection of recycled jars or drinking glasses is a great start to making a cutting display. There are many plants that can be propagated in water. The most common these days are houseplants like philodendrons, pothos, monsteras, African violets and ZZ plants to name a few. The sky is the limit – use all the same type of glass container or mix it up with different heights, sizes and colours. You can also get plant propagation stations online or in stores that are decorative, just waiting for water and cuttings. It’s a great way to watch plants grow and form roots while also filling a decorative role.

READ MORE: Learn how to make your own pots!

The Gardener