Plant Pots & Trays
Whilst plant pots are generally used to cultivate and display plants both indoors and out, smaller versions are also useful for sowing and raising young seedlings.
Shape
Plant pots generally come in two basic shapes: square and round. Whilst round pots are more traditional, square versions hold more compost and may be packed closely together to save space. Make sure that you choose a pot with sloping sides, as this will allow the plant and its root ball to be removed easily for repotting or planting out.
Size
Standard pots are as wide as they are deep, although many other variations may be found:
- Seed pans: Depth is one third the diameter - useful for germinating seeds.
- Half pots: Depth is half the diameter - useful for plants with relatively small root balls, such as evergreen azaleas.
- Long Toms: Depth is a quarter to a third longer than the diameter - useful for plants that require a long root-run, such as alpines or lily-of-the valley.
Materials
Plant pots are traditionally made from clay, although plastic pots are now far more common. The characteristics of both are described in the table below.
| Characteristic | Plastic Pots | Clay Pots |
|---|---|---|
| Cost | Cheap. | More expensive. |
| Weight | Light. Good for places such as shelves or balconies. |
Heavy. Good for large plants that might be top-heavy in a plastic pot. |
| Durability | Good. May eventually crack or split. |
Breakable. May flake or crack unless frost-proof. |
| Porosity | Impermeable. Compost will dry out more slowly than in clay pots. |
Porous. Compost less likely to become waterlogged. Plants may need to be watered more frequently. |
| Cleaning | Easy. | Difficult. |
| Other | Available in a range of colours. | Good for alpine plants (provides excellent drainage). |
When choosing a container, bear in mind that plastic pots made purely from polypropylene can become very brittle in cold weather, and so are not particularly suitable for growing plants outdoors. Instead, choose a pot made from a mix of polypropylene and polythene as this will not deteriorate in the cold.
Polythene pots are flexible, which allows them to be folded flat for storage. When filled with compost they become free standing, and are useful for pricking out seedlings prior to planting out.
Biodegradable pots are generally made from a mixture of recycled paper or wood fibre, peat and basic nutrients to help plant growth. These pots are excellent for plants that dislike having their roots disturbed as the pot may be planted directly into the soil. The pot then slowly degrades, allowing the plant's roots to grow out through sides and base into the surrounding ground. Gardeners can make their own degradable pots by forming cones from double-thickness newspaper.
The Egyptian pharoah Ramses III was the first to popularise, if not invent, flower pots, around 1230BC.
Plant Pot Saucers
Saucers can be very useful for catching excess water when watering plants or may also be filled to water plants from below. They are available in clay or plastic and may be bought in a set with the plant pot so that they match. After watering, make sure that you empty the saucer to prevent the soil in the pot from becoming waterlogged.