Supermarket hacks: five supermarket staples you can regrow for free

While the cost of living and food prices keep rising, there are steps you can take to reduce your supermarket bills – and this can start at the supermarket itself. Did you know some vegetables can regrow from scraps and shoots, while living herbs just keep on giving with a little nurturing? All you need is a windowsill with good light, some containers such as old mushroom punnets, and a bit of compost, and you can enjoy an amazing range of delicious, money-saving crops that are great fun and easy to grow. So, why not redirect your food waste into new food crops? You can start today.

Plant up your carrot tops

The tops of root crops like beetroot, carrot and turnip, readily regrow to produce leaves that are great for using in salads, soups and stews, or feeding to veg-loving pets like guinea pigs and rabbits.

1. Using a sharp knife, slice around 2-3cm off the top of the vegetable.
2. Put the cut top in a container with just the very base in water. Foil or plastic food trays, well washed, are ideal to use.
3. Place in a warm spot that gets sun for at least half the day and harvest as needed.
4. To harvest leaves over a longer period, transfer the tops into shallow trays of moist compost.

Keep watercress growing

This green leafy superfood is super-quick to grow, either in water or growing in compost that doesn’t dry out.

1. Set aside a few healthy green watercress shoots, and rinse well.
2. Remove the leaves on the lower quarter to third of each stem, and place the leafless section in water.
3. Replace with fresh water regularly.
4. Once rooted and growing well, pinch off shoots regularly to use.
5. To harvest over a longer period, plant the rooted shoots into shallow troughs or wide pots of compost 8-10cm deep, and water regularly to keep moist. Keep under cover in an unheated greenhouse, polytunnel, porch, or cold frame.

Grow new stems from celery and bulb fennel

The roots of these bulbous vegetables can not only produce new leafy growth but sometimes even small sticks or bulbs.

1. Slice off the main part of the sticks or bulb, keeping a good-sized portion of the base plate intact.
2. Place the the base in water and keep in a warm sunny spot indoors.
3. New growth should start appearing within a week. Either harvest little and often as required, or leave to develop further.
4. From late spring to summer, plant out in the garden to enjoy even more harvestable shoots. Acclimatise to the outdoors first, by placing outside for increasing periods over a couple of weeks, before planting in a sunny sheltered site.

Plant up your onion tops

The bases of onions and spring onions can resprout to produce edible, leafy growth to use in salads or cooked dishes.

1. Cut a 2-4cm section from the root end of spring onion bulbs. It's very easy if you buy fresh ones with the roots still attached. Simply place in a glass or jar in a little water.
2. For bulb onions, leave the cut bases to dry out for a couple of days, out of direct sun (onions can be a bit whiffy so you may prefer to do this part outside, so long as the weather isn’t frosty). Then pot into a shallow container of soil, water sparingly, and wait for the magic to happen.

Tip: always use a sharp knife to make clean cuts, as a blunt blade will crush or bruise the bulbs, reducing their chance of growing.

Grow on supermarket herbs

Supermarkets sell a range of popular potted herbs but look closely and you'll see that these are actually pots of seedlings crammed in together. They usually don’t survive for long. If you split them up and pot them up with more space to grow, you'll have lots more plants to eat for longer. You’ll need pots or recycled food containers with holes made in the base for drainage, and some peat-free multi-purpose potting compost.

1. An hour or so before splitting it, water your supermarket herb if the compost is dry. Spread out some newspaper on your work surface and gently remove the pot.
2. Use your fingers to gently separate the clump into several pieces. Discard any dead, yellow, or wilting leaves or seedlings.
3. Plant each piece into its own pot of compost, ensuring the soil level is the same as where the young herbs were growing previously. Firm the compost gently around the roots and water well.
4. Keep sun-loving herbs like basil and coriander on a warm, sunny windowsill, and shade-loving herbs like parsley in a cooler spot with less sun.