Regrowing Vegetables from Kitchen Scraps

Before you scrape the chopping board into the food caddy, stop. Some of those bits you would normally bin are alive — and given a little water and a sunny windowsill, they will sprout fresh green leaves within days. Regrowing vegetables from kitchen scraps is one of the best ways to get children growing, because it costs nothing, needs no garden, and something visible happens almost straight away. No waiting weeks for a seed to wake up.

This is a brilliant rainy-day project for a Saturday afternoon, and it teaches a real idea: that a plant is not a one-off, and that the part left in the bottom of the salad drawer still wants to grow. Here are the scraps that genuinely work, the ones that are just good fun, and how to keep the winners going. For lots more easy starter projects, head back to our getting kids growing guide, the home of all our family growing ideas.

Spring onions in a glass of water

If you only try one thing on this list, make it spring onions. They are the fastest and most reliable scrap of the lot, and children love how quickly the change shows.

Next time you use spring onions in a salad or a stir-fry, keep the bottom 3–4cm — the white root end with the little hairy roots still attached. Stand them upright in a small glass with just enough water to cover the roots, leaving the cut tops poking out into the air. A clear glass is best so your child can watch the roots grow too.

Put the glass on a bright windowsill and change the water every couple of days so it stays fresh and clear. Within two or three days you will see new green growing up from the middle. Within a week or so you will have a whole new set of spring onions, ready to snip again.

This one is so easy it almost feels like cheating, which makes it a perfect first win for a slightly impatient child. It pairs beautifully with our other quick windowsill projects like growing cress and sprouting seeds and microgreens.

Lettuce, celery and pak choi from the base

Lettuce, celery and pak choi all regrow the same clever way: from the solid base where the leaves join. Instead of binning that stump, you give it a drink and it sends up a fresh rosette of leaves from the centre.

When you have used up a head of celery, a Little Gem lettuce or a pak choi, keep the bottom 4–5cm — the firm root end. Sit it cut-side-up in a shallow dish or saucer with about 1–2cm of water in the bottom. You are not covering the whole thing; just keeping the base wet. Pop it on a windowsill that gets good light.

Change the water daily, or every other day at least — celery and lettuce bases can turn slimy if the water goes stale, and nobody wants that. Within three or four days you will spot tiny new leaves unfurling from the very middle. Celery is especially satisfying because the new feathery growth looks so different from the chunky stalks you started with.

Once the base has rooted and put out leaves, you can pot it on and keep it going properly. If your child gets the bug for salad, our full guide to growing your own lettuce takes it from windowsill scrap to a proper crop you can pick all summer.

Carrot and beetroot tops

This is the one where being honest with your child really matters. When you chop the leafy top off a carrot or a beetroot, that little stub will happily sprout fresh green leaves — but it will not grow a new carrot or beetroot. The root you ate is gone for good. What regrows is the leafy top, not the vegetable.

That is still worth doing, because carrot tops are genuinely pretty — fine, feathery and fern-like — and the young leaves are edible, with a fresh, slightly carroty taste that is nice chopped small into a salad. Beetroot tops grow into pinkish-stemmed leaves you can use like baby chard.

Keep the top 2cm of a carrot or beetroot, sit it cut-side-down in a shallow dish with a little water touching the base, and put it on a windowsill. Green shoots appear from the top within a few days. Change the water regularly to keep it sweet.

If your child wants to grow an actual carrot, that comes from seed, not scraps — and it is easier than people think. Our carrots guide shows you how, and it is a great next step once they have caught the growing bug.

Supermarket herb pots

That sad little pot of basil or parsley from the supermarket is not really one plant — it is dozens of tiny seedlings crammed together, all fighting for the same thimble of compost. That is why they tend to flop and die within a fortnight on the kitchen windowsill. The fix is to split them up.

Tip the pot out gently and you will see a dense mass of roots. Tease it into two, three or four clumps with your fingers — a lovely, slightly messy job for small hands — and pot each clump into its own small pot of fresh peat-free compost. Given more room and a little space to breathe, each clump grows into a far stronger, longer-lasting plant.

Water them in, keep them on a bright windowsill out of cold draughts, and pick little and often rather than stripping a whole plant at once. Basil likes warmth, so a sunny kitchen sill suits it; parsley, coriander and chives are tougher and happy in cooler light too.

Splitting and potting on is a proper bit of gardening, and it is the perfect bridge from "scraps in a dish" to growing things in containers for real. Our guide to windowsill growing covers light, watering and the best crops for an indoor sill, so your child's herbs keep going long after the supermarket version would have given up.

Sprouted potatoes and garlic

Reach to the back of the cupboard and you will eventually find a potato sprouting pale shoots, or a clove of garlic that has pushed up a green spike. Both are the plant trying to grow — and both can be planted.

A sprouted potato can be planted in a deep pot or a sack of compost, sprouts pointing up, and covered with 10cm of compost. Keep adding compost as the leaves grow (children love "tucking the potatoes in"), keep it watered, and a few months later you tip the whole lot out to hunt for new potatoes — an excellent treasure-hunt finale. Spring is the natural time to start in the UK.

A sprouted garlic clove can be pushed into a pot of compost, pointed end up, just below the surface. It will grow into green garlicky shoots you can snip like chives, even if it never forms a big bulb. The fresh shoots are tasty and the project is foolproof.

What genuinely works versus what is just fun

It helps to be straight with children about which scraps reward you and which are mostly a bit of fun. Here is the honest scorecard.

Genuinely works (regrows something useful):

• Spring onions — regrow fully, again and again. The star.
• Lettuce, celery, pak choi bases — give a real flush of fresh leaves, and grow into proper plants if potted on.
• Supermarket herbs — split and potted, they become strong, lasting plants.
• Sprouted garlic — reliable green shoots to snip.

Fun, but manage expectations:

• Carrot and beetroot tops — pretty, edible leaves, but never a new root.
• Sprouted potatoes — can crop, but shop potatoes are a gamble; seed potatoes are better.
• Avocado stones, citrus and apple pips — these aren't scraps in the same way and belong in our growing pips and stones project. Be honest: they grow into fun houseplants but very rarely fruit in the UK climate.

Knowing the difference is part of the learning. A child who understands why a carrot top makes leaves but not a carrot has grasped something real about how plants work — and that beats a false promise every time.

Moving the keepers into compost or soil

Water gets a scrap started, but it can't keep it going forever — there are no nutrients in plain water, so eventually growth stalls. To turn a rooted scrap into a lasting plant, move it into compost once it has a decent set of roots and some new leaves, usually after a week or two.

Half-fill a small pot with peat-free compost, sit the rooted base on top, fill in around it so the roots are covered but the growing point stays at the surface, and firm it gently. Water it in. Keep spring onions, lettuce and celery on a bright windowsill or, once the weather is mild from late spring, harden them off and move them outside.

This is the moment your scrap project becomes real gardening — and a natural doorway to growing food properly. If your child is keen to keep going, our guides to easy crops for kids and growing food in containers are the obvious next steps, and the whole Gardening with Children hub is full of projects to try next.

Whatever you grow, the real win is the same: a child who looks at a vegetable and sees something alive, not just something on a plate. Save a few scraps this week, stand them on a sunny sill, and let them watch what happens. For more free, foolproof ideas to do together, come back to our getting kids growing guide any time.