Regrowing – allowing leftover vegetables to grow back

1_Stockfood_PhotoCuisine_60428400 — Pineapple, lettuce, leeks, avocado and fennel can all continue to grow or turn into new plants in water.

Vegetable scraps such as lettuce stalks, leek root pieces and carrot ends are regularly produced in the kitchen when cooking and preparing meals. These leftovers usually end up in the organic waste or, at best, in the compost or, to save space, in a Bokashi bucket. But did you know that you don't actually have to throw away all of your leftovers? Regrowing is an increasingly popular method in which you can grow new, delicious greens from leftover vegetables. All you need is a container, water, possibly toothpicks and sometimes a little potting soil, and of course leftover vegetables. After a while they sprout again and provide you with fresh greens and an exciting experience. You can store your vegetables in home-made wooden boxes.

That way you can bring more sustainability into your home, whether you live in the country or in a small city apartment. Upcycling from waste is can also be done with food, you produce less waste and grow your edible urban jungle. We'll explain how it works.

2_GettyImages_Westend61_1742913496 — To keep your vegetables fresh longer or to keep them growing, you can put them in a little water.

The basics

The regrowing method works very well with carrots, lettuce, cabbage, leeks, onions, spring onions, beetroot and celery. But lemongrass or turmeric and ginger roots also sprout fresh greenery if handled correctly and can be used one or more times. The principle is simple: First place your cutting waste, root residues and stems in a container with a little water. This pure water culture works really well, especially with leeks. After a while, the vegetable residues form new roots and sprout again. For most other vegetable scraps, to get a good harvest, it makes more sense to transplant them into a container with potting soil once they have sprouted roots. The explanation is obvious: Potting soil contains nutrients that water cannot provide – and nutrients are important for plant growth. If you just put your leftovers in water, you will also harvest greens, just not as many.

Your different vegetable scraps prefer different conditions to grow well: Exotic plants such as turmeric and lemongrass love warmth and light. Onions, leeks and other local vegetables are a little less demanding and are also happy with normal room temperatures.

3_FloraPress_LizEddison_00761186 — Growing new greens: You can grow delicious carrot greens from the small carrot stump. They taste great with everything that you would otherwise season with parsley.

Planters

Water glasses are well suited to start with, whether a vase, drinking glass or preserving jar. If you want to continue cultivating in soil, old tomato or soup cans which you might have at home are ideal. Tetra bricks can also be used for this purpose. Using these kinds of containers even adds an upcycling component to regrowing. However, you have to be careful that it doesn't get too wet in the pot or that it doesn't become waterlogged. Plants, and of course vegetable scraps, don't like that at all. To prevent this from happening, you can poke two to three small holes in the bottom of the containers so that excess water can drain out. Place the regrow pot on a saucer to avoid water stains. We'll explain how to properly plant a pot here.

4_GettyImages_ElvaEtienne_1220350327 — How much life there is in the greens on the supermarket shelf also fascinates children and certainly encourages the little researchers to eat vegetables.

Leeks and spring onions

You will quickly achieve success when regrowing leftover leeks and spring onions. Don't cut the leek or spring onion stalk too close to the root base; there should be 1-2 cm remaining. Don't wait too long to regrow, the roots shouldn't dry out. Put some water in a glass and place about 2-3 leek stalks next to each other. Only the roots, but not the base of the leek, should come into contact with the liquid, otherwise the leek leaves would rot. So either just put some sediment into the glass or stick toothpicks all around the vegetables and suspend them in the glass so that the roots reach into the water. After just 1-2 days you will see new leek greens forming. Change the water every two days and after a week you can harvest your home-grown leeks.

5_GettyImages_Westend61_1742907896 — If an onion sprouts, there is no need to throw it away. You can simply plant them and use the delicious onion greens like spring onions. Broccoli doesn't grow back, but stays fresh and crunchy longer in water – including the very tasty stem.

Onions and garlic

Onions and garlic are almost indispensable in the household. They are peeled before further processing and the roots are removed. There should be 1-2 cm of the bulb left for regrowing. You can let the onion cutting continue to grow in the water glass as described for the spring onions. But it also works with soil: For this, fill a pot with potting soil and stick the onion into the soil root first so that everything is covered. Always keep the soil moist, but definitely not too wet. In a bright spot, your onion greens will be ready to harvest after a few weeks.

6_iStock_pundapanda_1758418563 — Carrots and beets of all colors are not only delicious root veggies, they also have delicious greens! You can easily let them grow a little in a small bowl of water and harvest them whenever you need them.

Carrots and beetroot

It is not widely known that the pretty leaves of beetroot and carrots can also be eaten. The tender young leaves in particular taste delicious – and you can easily grow them yourself from your leftover vegetables. To do this, use the beet head, which is cut off when preparing carrots and beets and otherwise thrown away.

This is how it's done: Cut off the beet head 1-2 cm below the green base and place several pieces in a bowl or glass with a little water. Only the lower part should be in the water. Keep it bright and warm and change the water every few days. After a week, new roots and the first greens will form. Now it's time to transplant it into a container filled with soil. Only part of it goes into the ground; the beet head should be visible. Keep the soil moist, but avoid overwatering to prevent it from waterlogging. This won't produce a new beet, but it will produce plenty of delicious greens for salads or pesto.

7_iStock_loorana_489775692 — Romaine lettuce is the most reliable type; it grows easily and crisply. On the left of the picture the celery is also a gratifying test subject.

Lettuce and cabbage

You can actually use all heads of lettuce and cabbage for regrowth, but it works particularly well with romaine lettuce. Before cleaning the lettuce, cut off the leaves about 3-5 cm above the lower end and place almost half of the stalk in a glass of water. The leaves should not get wet. Once the first tender roots have formed after a few days, plant the stalk in a container filled with soil deep enough so that the leaves stick out, or leave the lettuce in the water. Sometimes a hard shoot with small leaves forms in the middle. This is a flower base and the leaves on it taste bitter. You should therefore break off this shoot. After a few weeks, large fresh leaves will form that will enrich your meals with lots of vitamins and nutrients. If a leaf begins to wilt, remove it with sharp secateurs, such as the EasyPrune secateurs from Bosch, so that the entire head does not start to rot. When harvesting, you can either cut off all the new greenery straight away or just the outer leaves. If the lettuce heart remains intact, fresh greens will grow back for a long time. Regrowing is not possible with flowering plants such as broccoli, cauliflower or Romanesco.

8_GettyImages_yortzafoto_1200724958 — If your lemongrass has not been cut too close and still has a tiny bit of roots left, you can put it in water, let it root and plant it.

9_FloraPress_BIOSPHOTO_Jean-MichelGroult_01888038 — If your lemongrass has not been cut too close and still has a tiny bit of roots left, you can put it in water, let it root and plant it.

Lemongrass

In terms of difficulty, lemongrass midfield when it comes to regrowing. In addition to light, warmth and patience, the most important success factors are that you have a piece of lemongrass that still has enough of the stalk left and not just the leaves. What you need are the lower parts of the stem, which should be around 5-7 cm long. Place them in some water that needs to be changed every few days. After 2-3 weeks, if the stems are in a warm place little roots will form. Now your rooted lemongrass can be moved into a container with soil. Don't plant it too deep, most of the greenery will stay above the surface. Fresh greens will gradually form, which you can cut off and use for tea, seasoning or desserts. There should always be enough of the plant left so that it is not weakened and you can continue to harvest for a long time.

A home-made herb rack is pretty . You can grow lemongrass in it decoratively, but also home-grown basil, mint or sage, which you can simply grow from cut sprigs.

10_iStock_bdspn_481089552 — Turmeric and ginger are often mistaken for roots, but they are rhizomes, i.e. underground shoots. If you have forgotten one of the plants and it sprouts, this is your opportunity to try growing it!

Turmeric and ginger

A bit of information in advance: Turmeric is a ginger plant – so you can regrow turmeric and ginger in the same way. By the way, they are not roots, but rather rhizomes, i.e. an underground shoot. They can be used in a variety of ways, for teas, golden milk and curry dishes. Actually everything from the rhizomes is used – there are not usually any leftovers. But if there is something left over or you just want to try out whether regrowing is successful, then give it a try and get started. The larger the piece that is to be planted, the greater the chances of success. What you still need is time. You don't have to put turmeric and ginger in the water; the piece goes straight into good potting soil about 5 cm deep. And because the ginger family originally comes from India, it is clear what they need most: Warmth. The pot should be placed somewhere that is around 24 degrees warm, and watered sparingly. You can ensure this in a mini greenhouse, for example. It takes at least three weeks until the first shoot emerges from the ground and from then on it wants to be nice and bright. Give the plant time to grow and thrive. In the cold and low-light season, the leaves will lose strength and eventually shrink. Then move the pot to a cool room and stop all care measures, including watering. Read about how to winterize potted plants here. From February/March onwards, start watering it again and put the pot back in a warm place. If everything went well, the rootstock will sprout again. With a bit of luck, new rhizomes will form after 1-2 years, which you can harvest in winter.

11_iStock_pundapanda_1758418560 — Of course, you won't be able to live off your regrown greens, but it's enough for a fresh and healthy ingredient!

Use

You probably won't be able to eat a whole meal by regrowing. But the fresh, tasty and healthy green is well suited as a topping for salads, soups and all dishes in general. You can also use your harvest in smoothies or for savory muffins. The great thing about it is that it is completely fresh and really contains a lot of healthy ingredients. The harvest doesn’t have to be that big. Quality comes before quantity. And sustainability is fun.

Even more interested in regrowing? Then try it with an avocado, olive or pineapple!

If your home-grown plants are suitable for planting out, you can also plant them in the garden or in a raised bed. Read about how you can plant it or build it yourself here. If you discover pests, we have 5 tips for you. And once your project has died off, put it in the Bokashi bucket, which is a mini compost – we'll explain to you how it works.

If you want to know more about when you should do what kind of work in the garden, you can find out the best times for all the important tasks in our Gardening Calendar.