Why growing your own vegetables is worth it in South Africa

We get asked a version of this question most weekends at the nursery. Someone is standing in front of a trough, holding a punnet of spinach seedlings, and they want to know, honestly, whether it is worth the bother. Is it cheaper? Does it taste different? Will they actually eat it? We have been growing food in pots on the Highveld long enough to give a straight answer, and the straight answer is yes, but only if you grow the right things in the right way. The rest of this article is the long version of that.

What follows is not a list of every benefit anyone has ever claimed for a veggie patch. It is the handful of things that have held up for us and for the customers who come back season after season, with real numbers where we have them and a few honest caveats where we do not.

The maths on a seed packet

Walk down the fresh produce aisle and a punnet of baby spinach or a bag of mixed lettuce costs roughly the same as a packet of seed for that same crop. The difference is that the punnet lasts three or four days and the packet holds a few hundred seeds. Sown a pinch at a time every fortnight, one packet of spinach or loose-leaf lettuce keeps a family in salad greens from September right through to the first Highveld frost in May. That is the saving in a nutshell. It is not on tomatoes, which need a long season and get hammered by hail and blight, and it is not on potatoes, which are cheap to buy and take up space. It is on the things you buy in small, expensive amounts and use constantly: leafy greens, herbs, spring onions, chillies, beans and baby marrows.

The saving also grows every year the shops get pricier. Stats SA publishes food inflation every month in its Consumer Price Index release, and fresh vegetables are one of the categories that swing hardest, because a drought, a hailstorm or a fuel price hike lands on the shelf within weeks. A pot of spinach on your stoep does not care what diesel costs this month.

Freshness you can actually taste

A supermarket lettuce has usually been cut, cooled, packed, driven to a distribution centre and driven again before it reaches you. It was probably harvested three to five days before you eat it. Leafy crops start losing water and sweetness the moment they are picked, which is why home-grown rocket bites and shop rocket often tastes of nothing. Herbs are the extreme case. Basil goes black within a day of the fridge; picked off a pot at the kitchen door it smells like the whole plant. Once you have eaten beans that were on the plant twenty minutes ago you understand why people bother.

Freshness has a practical side too. Vegetables you pick as you need them do not sit wilting in the crisper drawer, so you waste far less. Most of the households we talk to throw away more salad than they eat. Picking a handful of leaves a night instead of buying a bag a week quietly fixes that.

Food that does not depend on the shops

South Africans have had a good education in the last few years about how fragile the supply chain is. Load-shedding empties supermarket cold rooms, a strike closes a port, a flood cuts a highway and the vegetable shelves empty first. A dozen pots of food will not feed a family, and we would never pretend otherwise, but a kitchen with its own greens, herbs, chillies and a lemon tree in a big pot is a kitchen that can always make a decent meal out of a bag of rice and a tin of beans. That is a different kind of security from the financial sort, and people who have tasted it tend not to go back.

Grow what your family actually eats

This is the place most first gardens go wrong. People plant what looks fun on the seed rack, then find themselves with forty brinjals and nobody who likes them. Sit down with a week of your grocery slips and circle the fresh things you buy every single time. For most families it is spinach or Swiss chard, lettuce, tomatoes, onions, peppers, herbs and maybe green beans. Grow those, in the quantities you use, and skip the rest until you have space to spare. The growing food in pots guide walks through the pot size and sun each of those crops needs, and the shorter container vegetable quick guide is a good one to print and stick on the fridge.

Spinach is the crop we push hardest at beginners because it is nearly impossible to fail with on the Highveld. Swiss chard shrugs off frost, produces for months, and a single trough of six plants supplies a small household. Loose-leaf lettuce is a close second in the cooler months. Herbs are the third, and basil, parsley, chives, mint and rosemary all behave themselves in a pot by the kitchen door.

The bit nobody sells you

There is a quieter benefit that we did not appreciate until we saw it in customers over the years. Ten minutes watering and picking in the early morning, before the phone starts, changes the shape of a day. This is not just a feeling. A meta-analysis in Preventive Medicine Reports pooled 22 studies and found gardening associated with lower depression and anxiety scores and higher life satisfaction. We are not going to dress that up as therapy. It is just a good reason, on top of the practical ones, to have something growing that you have to go and look at every day.

Why pots beat beds for most South African gardens

Almost everything that makes vegetable growing hard here is easier in a pot. Highveld frost kills seedlings in open ground in June; pots can be shuffled against a north wall or under the eaves for the cold weeks. Summer thunderstorms bring hail, and a trough of lettuce can be dragged under cover in the two minutes before it hits. Clay soil in Gauteng and sandy soil in Cape Town both need years of work to grow good root crops, while a pot is filled with the right mix on day one. When water restrictions come around, a pot uses a fraction of the water a bed does because none of it runs off into the lawn and a mulched pot holds what you give it.

Pots also solve the sun problem in townhouse complexes and on balconies. Fruiting vegetables such as tomatoes, peppers and beans need at least five hours of direct sun and prefer eight, while leaf crops tolerate some shade, as Clemson University's container vegetable gardening factsheet lays out. In a shaded yard you put the spinach where it is and move the tomato pot to the one sunny corner. You cannot do that with a bed.

Which pot for which vegetable

Depth and volume matter more than anything else. Shallow-rooted crops like lettuce, spinach, rocket, spring onions and most herbs are happy in a long concrete trough, which also gives you a row you can sow in stages. Something like the Curo trough takes six spinach plants comfortably. Tomatoes, peppers, brinjals and dwarf beans want a single deep pot each, around 40 to 50 litres, so the roots stay cool and the soil does not dry out by lunchtime in January. Concrete helps here. Our pots are cast from Fibre Concrete Mix, which keeps the root zone noticeably cooler than a black plastic pot in full Highveld sun and does not blow over in an August wind. The whole range that suits food is gathered in the herb and vegetable pots collection.

Get the soil right and the rest is easy

Vegetables are greedy, and a pot has no reserve to draw on. Never fill a food pot with garden soil; it compacts into a brick and drowns roots, which we explain in can garden soil be used in pots. Use a proper bark-based outdoor potting soil and mix in a third by volume of compost before planting. Top the pot up with a few handfuls of compost every couple of months through the season, because watering washes nutrients out of the bottom. The University of Georgia's home vegetable gardening guide makes the same point about steady feeding for heavy croppers like tomatoes, and it applies double in a container.

So, is it worth it? For the salad, the herbs, the chillies and the beans, yes, quickly and obviously, and for the food security and the ten minutes of quiet in the morning, yes in ways that are harder to put a rand value on. Pick the crops your family really eats, give them deep pots or a trough in real sun, and start this weekend. The herb and vegetable pots are the ones we plant up ourselves.

Frequently asked questions

Is it cheaper to grow your own vegetables in South Africa?

For leafy greens, herbs, spring onions, chillies and beans, yes. A seed packet costs about the same as one supermarket punnet and holds enough seed for a whole season. Crops like potatoes and onions are cheap to buy and rarely save money at home.

Which vegetables are easiest to grow in pots for beginners?

Swiss chard and spinach, loose-leaf lettuce, rocket, spring onions and most herbs. They tolerate some shade, cope with Highveld frost and give a harvest within six to eight weeks.

How much sun do vegetables in pots need?

Fruiting crops like tomatoes, peppers and beans need at least five hours of direct sun and do best with eight. Leafy crops manage in four to five hours or bright dappled shade.

Can I use garden soil in a vegetable pot?

No. Garden soil compacts, drains badly and starves roots of air in a container. Use a bark-based outdoor potting soil mixed with about a third compost, and top up with compost through the season.

What size pot do tomatoes need?

One plant per deep pot of roughly 40 to 50 litres. Smaller pots dry out by midday in summer and produce far less fruit. Lettuce, spinach and herbs are fine in a long trough.