Container Gardening 101: Choosing the Right Pots and Soil

If your plants are the actors, then pots and soil are the stage and script. You can have the most beautiful basil seedling in the world, but if it's sitting in compacted garden dirt inside a pot with no drainage holes, it's going to have a very short career. I've seen this happen more times than I can count, and it's always the same story: wilting leaves, yellow stems, and a disappointed gardener wondering what went wrong.

The truth is, choosing the right containers and soil is half the battle in container gardening. Get these two things right, and everything else — watering, feeding, even pest management — becomes dramatically easier. If you're just getting started, pair this guide with my balcony garden beginner's guide for the full picture.

Understanding Pot Materials

Every pot material has trade-offs. There's no single "best" option — the right choice depends on your climate, your plants, and how much effort you want to put into watering.

Plastic Pots

Plastic is the workhorse of container gardening. It's lightweight, inexpensive, retains moisture well, and comes in every size and colour imaginable. Modern plastic pots can look surprisingly stylish, and their light weight makes them ideal for balconies where every kilogram counts.

Terracotta Pots

Terracotta is the classic choice, and its warm, earthy appearance is hard to beat. The porous clay allows air and moisture to pass through the walls, which helps prevent root rot and provides excellent aeration. However, this same porosity means soil dries out faster, so you'll need to water more frequently.

Best For: Drought-tolerant herbs (rosemary, thyme, sage, oregano) that prefer drier conditions. Avoid terracotta for moisture-loving plants unless you're prepared to water daily in summer.

Fabric Grow Bags

Fabric pots have become incredibly popular in recent years, and for good reason. They provide exceptional drainage and air-pruning of roots — when roots reach the fabric edge, they stop growing in circles and branch out instead, creating a healthier root system. They're also very lightweight and fold flat for storage.

Best For: Tomatoes, peppers, potatoes, and any plant that benefits from deep root systems. They dry out faster than plastic, so plan on watering more often. Sizes from 10 to 40 litres are most practical for balcony use.

Glazed Ceramic Pots

Glazed ceramic offers the beauty of terracotta without the rapid moisture loss. The glaze seals the porous clay, so water retention is similar to plastic. They're heavy though — a large glazed ceramic pot filled with wet soil can be extremely weighty.

Best For: Feature plants and decorative arrangements. Their weight makes them stable in wind but impractical for moving around frequently. Best placed near walls for weight distribution on balconies.

Choosing the Right Pot Size

Pot size directly affects how well your plants grow. Too small, and roots become cramped, water evaporates too quickly, and the plant struggles. Too large, and excess soil stays wet around a small root ball, which can lead to root rot.

When in doubt, err on the side of a slightly larger pot. The extra soil volume holds more moisture and nutrients, gives roots room to grow, and means you won't need to water quite as often. Just make sure the pot has adequate drainage so excess soil doesn't become waterlogged.

The Golden Rule: Drainage

If there is one non-negotiable rule in container gardening, it's this: every pot must have drainage holes. Without them, water collects at the bottom, roots suffocate, and fungal diseases set in. I don't care how beautiful a pot is — if it doesn't have drainage, either drill holes in the bottom or use it as a decorative outer sleeve with a well-drained inner pot.

Choosing the Right Potting Mix

Never, ever use soil dug from your garden in containers. Garden soil is too dense, compacts in pots, drains poorly, and often carries weed seeds, pests, and diseases. Instead, use a purpose-made potting mix (also called potting compost or container mix).

What's in Good Potting Mix?

A quality potting mix typically contains three main components:

• Peat moss or coconut coir — holds moisture and provides structure. Coir is the more sustainable option and works just as well.
• Perlite or vermiculite — lightweight volcanic minerals that improve drainage and aeration. Perlite is the white granules you see in most mixes.
• Compost or organic matter — provides nutrients and beneficial microorganisms. Well-rotted compost is ideal.

For most balcony plants, a standard multi-purpose potting mix works perfectly. For Mediterranean herbs and succulents, mix in extra perlite (about 30 percent by volume) to improve drainage. For tomatoes and hungry fruiting plants, choose a mix enriched with slow-release fertiliser or add your own.

Refreshing and Reusing Soil

At the end of each growing season, don't throw away your potting mix. Remove any dead roots and debris, then refresh it by mixing in about 25 to 30 percent fresh compost. Add a handful of perlite if the mix has become compacted. This revitalised mix is perfectly good for another season of growing.

With the right pots and soil in place, you've built a strong foundation for everything that follows — whether that's a windowsill herb garden or a full balcony vegetable plot. Ready to get planting? My guide on the best herbs for your balcony is a great next step, or jump straight to growing tomatoes in containers if you're feeling ambitious.