Starting a Small Vegetable Patch in Containers

Why a Patio Patch Is Worth the Effort

You do not need a plot, a rotavator or even a patch of soil to eat something you have grown yourself. A sunny patio, a balcony with a bit of shelter, or the paved corner by the back door will do perfectly well. Containers give you control: you can move them out of the wind, raise them to a comfortable working height, and fill them with fresh compost rather than inheriting whatever your soil has been doing for the last forty years.

The trade-off is that pots dry out faster, heat up faster and run out of food sooner than open ground. Get those three things right and you will be cutting your own salad leaves within six weeks of sowing.

Choosing Pots and Getting Drainage Right

Size matters more than style. As a rough guide:

• Salad leaves and herbs: 15–20cm deep, roughly 5 litres per plant.
• Dwarf French beans: 25–30cm deep, 10 litres or more per plant.
• Tomatoes and chillies: 30–40cm deep, 15–20 litres per plant.

Terracotta looks lovely but dries out quickly in sun. Glazed ceramic and plastic hold moisture far better, and a light-coloured pot keeps roots cooler in a hot spell. Whatever you choose, it must have holes in the bottom — several, not one. Drill them yourself if needed, because a pot without drainage is a bucket, and roots sitting in stagnant water will rot within days.

Stand pots on feet or bricks so the drainage hole is not sealed against the paving. A saucer is useful in dry weather, but empty it after heavy rain. If you are on a balcony, check the weight: wet compost is heavy, and a row of large pots adds up quickly.

Compost, Feeding and a Bit of Grit

Use a peat-free multipurpose compost as your base. For crops in the ground for months — beans, tomatoes, peppers — mix in a handful of soil-based compost and a slow-release fertiliser to give them something to draw on.

Herbs are the exception. Rosemary, thyme, sage and oregano come from rocky Mediterranean hillsides and resent rich, soggy compost. Mix in plenty of horticultural grit or perlite, roughly one part grit to three parts compost, and water sparingly.

After four to six weeks, most crops will have used up the food in the compost. Start liquid feeding weekly: a general-purpose feed for leafy crops, and a high-potash tomato feed once beans and tomatoes begin to flower.

What to Sow, and When

Start modestly. Three or four pots of things you actually eat beats a forest of seedlings you cannot keep up with.

• Cut-and-come-again salad: sow thinly on the surface, cover lightly, and start cutting when leaves reach 8–10cm. Sow a small pot every two to three weeks from March to September for a continuous supply.
• Herbs: basil, parsley, chives and coriander all thrive in pots. Basil loves warmth; coriander bolts in heat, so give it a little afternoon shade.
• Dwarf French beans: sow two or three seeds per 10-litre pot in late May, once the soil has warmed. They crop for weeks and need no staking.
• Radishes and spring onions: quick, forgiving, and ideal for filling gaps between slower crops.

Keep a fleece or cloche handy. A late frost in May will see off tender seedlings overnight, and a sheet of horticultural fleece costs far less than starting again.

Watering: The Job That Makes or Breaks It

In a British summer, a container can dry out in a single warm afternoon — more if it is windy, because wind pulls moisture from leaves faster than sun alone. Check daily by pushing a finger two knuckles deep into the compost. If it is dry at that depth, water.

Water thoroughly until it runs out of the bottom of the pot, rather than giving a light sprinkle every day. A little and often only wets the surface and encourages weak, shallow roots. Water in the morning if you can; evening watering leaves foliage damp overnight, which invites mildew.

Two easy tricks cut the workload: spread a 2cm layer of gravel or compost mulch over the surface to slow evaporation, and group pots together so they shade one another. If you are away, move pots into shade and stand them in a tray of water.

Pests, Weather and Keeping Things Tidy

Slugs and snails are the main enemy of young seedlings. Go out after dark with a torch, or use a nematode drench in spring for a longer-term solution. Barriers of wool pellets or crushed eggshell help, though a determined snail will find a way.

Otherwise, most problems come down to weather. Too much rain waterlogs pots and splits tomatoes; a heatwave brings aphids and whitefly. Check the undersides of leaves weekly and squish or spray with a dilute soap solution.

Finally, pick often. Regular harvesting keeps salad leaves tender, stops herbs from flowering and keeps beans producing. A container patch rewards attention more than it rewards space — half an hour a week is usually enough.