Terrariums and Mini-Gardens

Terrariums and Mini-Gardens
A Terrarium can be lots of fun to grow and makes for an enjoyable gardening project for all ages. Essentially it is a miniature garden grown under glass where plants used like high humidity. It is a self-catering ecosystem. In the case of the Desertarium, the plants used are usually succulents.

Containers, plants, soil, aquarium pea gravel, activated charcoal, peat moss or net divider, misting spray bottle, pebble mulch for decoration. If you are going to use decorative elements or ornaments, use anything that will not discolour, disintegrate or rust.


• You can buy custom-made terrarium containers or Wardian cases, but you can use old fishbowls, aquariums, glass bowls or bell jars, there are many ideas to choose from.
• When repurposing any container like a fish bowl, cleaning it is very important. Use hot soapy water to wash vigorously, rinse twice with a vinegar/water solution and then once again with hot steamy plain water. Turn it upside down on a cake rack and let it dry naturally.
• Make sure your container is large enough to take the plants you choose – some ‘terrarium’ plants can grow up to 24 inches and more.

Plant shape, colour, size, purpose, growing manners, theme, fixings, time allocated to maintenance and style all play their roles. The important thing is not just to plonk any old plant any old where and say there, I did it! Think about your project, mix and match your plant choices well, leaf colours and textures and size and spread will give you an unending palette – so be mindful and let nature thrill. Watch out for proportions – go for the third third third balance … a third for soil or growing medium, a third or so for the plants and the last third for air space – this will result in a pleasing arrangement.

Plants that are naturally small and slow growing work best, choose like-minded plants that need similar conditions to grow. Your garden centre or nurseryman will give you good advice. Check the plants are disease free, remove shrivelled or yellow leaves and loosen roots before planting.

It’s easy if you follow the rules!
• It is very important that you get your growing medium and soil right. What you need to put it all together is pea gravel and activated charcoal (buy from a pet store), moist pre-mixed sterilized well-draining potting (not garden) soil, a nylon divider to stop the soil from mixing with the charcoal and gravel (or you can use a layer of peat moss).
• First, put a layer of gravel into the bottom of your container adding enough to go with your design and anyway at least an inch plus.
• Then add a layer of activated charcoal. These two layers ensure that your terrarium ‘smells’ sweet and that the roots of the plants will not rest in water and rot.
• On top of these place your layer of netting or moss which in turn will stop the soil from settling down into the bottom of the pot.
• Then add your soil (as much as you need for your container size and design) but at least 5 inches. If you wanted to here, and you have space, put a rock inside or create some hills and valleys for added interest.
• Add your plants, settle them in and water slightly and mist the leaves where appropriate. Remember you used moist soil and the plats will be moist as you take them out of their pots, so very little water is needed. If you have built your terrarium well, then it only needs light and warmth to prosper … the plants will recycle the moisture they use.

Watch out for:

*over or under watering:
*unruly or dying or diseased plants;
*wrong selections of plants for the type of terrarium you are growing,
*fertilizing too much or too often (hardly necessary in terrariums);
*dirty containers … keep them clean both inside and out and only use water for this job, residues from soaps and other cleaning agents will kill your arrangement;
*planting succulents in closed terrariums
*too much or too little light;
*leaving them in direct sunshine, don’t do this as they will overheat and the plants will die;
*placing them near heaters or radiators and finally,
*allowing the plants touch the interior glass – go for air spaces to assist with adequate condensation.

*How long does a terrarium last?
That depends! Not an easy question to answer as there are so many factors to take into consideration (plants, care, conditions and so on) but they can last for years, yes, years.

*Is glass better than plastic for containers?
Neither one is better than the other – it just depends on what you want and what you have available. Glass is heavier and will not scratch for instance, but plastic containers come in different shapes and are easy to move around. It is just a matter of choice,

*What about fertilisers for terrariums?
Are not really necessary as the plant material you used should have been healthy and vigorous and you do not want your plants to grow too quickly or it defeats the purpose of your terrarium Still, if you do think your plants may need a boost, use a liquid foliar fertilizer which you can mist on, then monitor the results.

*How will I know if I have overwatered?
You will notice water at the bottom with the gravel and your terrarium may be smelly. Your plants will also be wilting and root rot may be apparent. Use a paper towel or twisted tissue to soak up extra water easily, if there is not too much. You can also open the lid to allow it to dry out for one or two days. However and sadly, if you need to, empty it out, save what you can of the plant material but throw everything else away and start again with fresh ingredients.

Let your imagination go walkies, get your friends involved, hold a terrarium party for older children – it will give much pleasure. I know a lady who has turned making these specialized gardens into a home-based business. I love them because I see them as living and ever changing pieces of art – such a pleasure.

What do you want your container garden to do?


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