How to grow radishes in the window box

You want to grow radishes in the window box and wonder what to look for? Here comes the answer and the best tricks!

Those who have a small balcony, do not have to give up homegrown vegetables. Even in the smallest space can be grown many varieties. The best example of this is radishes.

Growing radishes succeeds directly in a flower box. Here you can also combine them with other vegetables such as lettuce, as long as you leave enough space.

Special growing soil, a growing pot or similar is not necessary. With a little sun, fresh soil and a little space, radishes can thrive magnificently in a window box - whether on the balcony, on the terrace or in front of the front door.

So much up front: growing radishes on the balcony is easy. All you need is soil, a sunny location, a planter and radish seeds. Thus, the little red balls are ideal for urban gardening beginners.

What you need to pay attention to if you want to grow radishes in a window box and how it is guaranteed to succeed, you can read now! Here are my self-tested tips and tricks for all hobby and urban gardeners.

What mistakes you can not make when growing radishes in the window box

Let's start with something negative right away 😄. With this, I want to prevent you from making the same mistakes I did and save you a lot of trouble.

Put the radishes too tight

I would like to tell you in advance about a mistake that all beginners make. I made it myself and wondered why instead of red balls only green leaves were visible.

You must not place the radishes too close together in the flower box. Between the individual seeds should be about 3 cm. This distance has proven to be optimal for me. This way, each plant gets enough sunlight and has room to form a fruit.

By the way, a growing pot and potting soil is not necessary. The radishes go directly into the balcony box and are happy with ordinary potting soil.

Do not press the earth

Yes, radishes need loose soil. But especially with potting soil, it is often the case that it is far too loose. So you really need to flatten it a little with your hands. The plants have only one root. With it, they cling to the soil so as not to fall over.

If the soil is too loose, they do not succeed. The formation of fruit turns out much less.

Therefore, when you grow radishes in a window box, you need to flatten the loose soil a bit. It is best to do this before sowing the seeds.

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Choose a shady location

Radishes need sun. If they get too little, they do not form tubers. All the energy goes into the greens. That can be made into smoothies - but really, we're all about the red, pungent tubers. So choose a location that gets plenty of sunlight.

Now that you know how not to grow radishes in the flower box, here come the tips that will be really useful to you.

What you need to know about soil and planter

Let's start right away with the most important. In order for your breeding to become something and you can look forward to a rich harvest, you need to know a few little things.

I have three tips for you that will make your life as a beginner easy.

The right flower box

I bought inexpensive flower boxes for the first tests. You can get them in any gardening store. For the next grows I resorted to a flower box with a built-in water tank. This has the great advantage that you do not have to water every day.

I can highly recommend a balcony box with water tank! But it also works quite well in a normal one - or with a large flower pot.

I have a classic flower box in use and am very satisfied with it. It has been planted for 5 years and thanks to good quality will surely last another 5 years. You can choose from different sizes and colors.

If you want to accommodate more plants, I can recommend this mini raised bed for the balcony instead of a conventional flower box. In it, there is additional space for herbs and lettuce, which, by the way, are wonderful plant neighbors for radishes and can even favor the formation of tubers.

Can you plant radishes in potting soil?

Yes, you can use potting soil for sowing. However, radishes feel more comfortable in vegetable soil. It contains better nutrients for growing vegetables.

Do not opt for the cheapest soil, tests have shown that the plants often do not thrive so beautifully in it. I can confirm this from experience! If you do take very cheap soil, help with a little liquid fertilizer, you can use the make your own from nettles.

Radishes like a light, water-permeable soil. They are among the weak growers and do not need too many nutrients like other plants. However, it is worthwhile to resort to high-quality soil.

I did a test last year and sowed lettuce in two flower boxes. In one flower box I used the cheapest soil from the discount store and in the other an expensive garden soil. The difference was enormous. So it's worth investing in good soil if you want to have a bountiful harvest.

Once you've caught plant fever, you'll soon be growing more than just radishes in your window box. Picking lettuces, onions, strawberries - they all grow wonderfully in the smallest of spaces. Take a look here: "How to grow strawberries in the plant box“

Even from an old salad drink can be made with a little skill pull a new salad.

How much soil do radishes need?

In order for them to thrive, you should fill the flower box to the top, leaving only 2-3 cm of margin. This will give you about 10 to 15 cm of soil, depending on the model. This is perfectly sufficient for the plants.

You should not use much less soil if you want to grow radishes. Otherwise, you will not keep up with the watering.

What are the seeds and varieties and which are suitable for the balcony?

Radishes come in different shapes, colors and sizes. From the red classics, to yellow elongated radishes to white, everything is there to make your vegetable patch colorful and varied.

In the supermarket you can usually buy only the classic radishes - red, round, large. If you like it a little fancier, you can also mix the seeds and be surprised.

There are varieties that grow faster and those that are specifically for cool temperatures. Read the description on the package and you will surely find the right variety for you.

You can choose from many seeds and varieties in garden stores. But you can also look online.

From my experience, I can say that radishes that grow elongated, do not do so well in the window box. It works best with radishes in the flower box, which are quite classic round - the color does not matter.

By the way, to grow radishes, in the flower box is very fast. So you can soon sow yourself a second balcony box - I leave about 14 days between pot 1 and pot 2.

What to look for when sowing radishes

Your fingers are already tingling? Well, then off to the balcony. Here you will find the most important answers to all questions about breeding.

When can you plant radishes?

Radishes are sown in spring temperatures. They are not very sensitive to cold. If the temperature falls below 10 degrees Celsius, you should bring the flower box indoors overnight if you want to harvest soon. As a guideline, the beginning of April. However, on very sunny balconies you can sometimes get started around mid-March.

If your balcony does not get so much sun, then you should wait until April. From May it is guaranteed to be warm enough so that the radishes in the flower box no longer need to go indoors at night.

In suitable weather, you can sow them outdoors from spring until the end of August. I still sow a pot in September - depending on the weather and temperature, sometimes it works quite well, another time unfortunately no longer.

How to plant radishes?

Radishes are always sown in rows. Between the rows is a distance of 7-10 centimeters. And between the seeds has proven successful for me a distance of 3 cm.

So in a flower box you can sow one row in the back and one row in the front. Or you can give the plants more space and sow only one row in the middle. Staggered sowing of seeds has also proven successful - in a zigzag pattern, so to speak.

You can buy radish seeds in a seed band or as individual seeds. If you decide to use individual seeds, place them on the soil first. Then press them into the soil with your finger. This way you can be sure that you have always chosen the right distance.

This approach has proven successful:

1. Fill the planter box with soil until there is about 5 cm of space at the top.
2. Moisten the earth
3. Lay out the seeds
4. Sprinkle a 1-2 cm layer of soil on the seeds
5. Press the earth with your hands
6. Place the flower box in a sunny, warm place

The germination period is only one week. Thus, radishes are among the plants that sprout the fastest.

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Do I need to transplant radishes?

The appropriate planting distance is important so that the roots and tubers can develop well. If you already pay attention to this when sowing and place the seeds individually, you do not have to separate radishes.

However, if you have sown too densely, you should prick them.

As soon as the first cotyledons appear, it is time to prick out (separate) the plants. To do this, carefully loosen the soil with your fingers and lift the plants out of the soil one by one. Now you put them back into the soil at a distance of 2 to 3 cm.

Where best to plant radishes?

Radishes feel most comfortable in a sunny and airy location. The soil should always be slightly moist. Whether grown in a flower pot, garden or radishes in a window box, it doesn't really matter. The main thing is that you give them enough sun.

Except in midsummer. Then you should have radishes in partial shade. Otherwise the leaves will burn and you will not be able to water them.

My experience with radishes has shown that they are best grown in the spring and fall. From growing them in the summer, I could never harvest much. Most of them shot up and did not form balls.

How to fertilize and care for radishes in the flower box?

The sharp, red tubers are very popular with beginners. No wonder, radishes are very unpretentious. You do not have to pay much attention to grow them.

Casting

Radishes in the window box need regular watering on warm days. If you water them too little, they become woody - that is, hard and fibrous. The soil must always be moist and should never dry out. Waterlogging, however, does not go down well. So you have to find a good middle ground.

That is why it is important that your planter has holes at the bottom. Otherwise, you will drown the plants.

Can you fertilize radishes with coffee grounds?

Radishes are weak growers. So they need few nutrients to grow. However, there are some vegetables that I have about Coffee grounds as fertilizer look forward to, like radishes or carrots. However, take for this very little coffee - fertilize once is more than enough.

If you use a high quality soil, you do not need to fertilize at all. If you plan to plant radishes in the same soil again, you can enhance it with a little organic fertilizer and apply a DIY plant fertilizer from nettles manufacture.

When do I know that radishes are ripe?

See how the radishes look out of the ground at the top? From a size of about 3 cm in diameter, they are ripe. About 30 days after sowing you can already harvest the first radishes. Do not leave them in the ground for longer than 6 weeks, otherwise they will lose their pungent taste and form flowers.

Therefore, you should think carefully about how many you really want and can eat. Therefore, I like to sow two flower boxes - between sowing I leave an interval of 14 days, so I have fresh radishes throughout.

Pull the radishes with the largest tubers out of the ground. The others you leave standing. They will love to have more space now and will also form tubers.

By the way, radishes taste best when freshly harvested. Just wash them and put them on your sandwich.

Grown too much? Taste this radish spread!

Crop rotation and mixed culture

Radishes belong to the cruciferous family and are therefore cabbage plants. In the same soil you should therefore only grow them again after 3 to 4 years, unless you enhance the soil with fertilizer.

Radish should not be sown in the same soil in which 3-4 years earlier grew representatives of the same family. These include kohlrabi, kale, broccoli, cauliflower, radish, white cabbage, Brussels sprouts, Asia salads and arugula.

Very good plant neighbors for radishes are

• Strawberries
• Salad
• Spinach
• Peas
• Carrots
• Beans
• Chard
• Cress
• Parsley

By the way, carrots and Runner beans good in flower pot breed and also Strawberries thrive in the planter box. 

Why radishes do not set fruit?

In principle, radishes are very easy to care for and thrive almost everywhere. However, if the soil is too firm, they do not form a tuber. They like humus-rich, well-drained, airy, light soil that is evenly moist. Hard, loamy soil or soil that is too dry will cause radishes to shoot up and flower quickly. Thus, no tubers are formed.

Also a problem can be when they get too little sun. Then the plants get such a stress that they do not care about the development of the tuber. All they then want to get over quickly is to bloom and multiply.

So if it doesn't work out for you in the garden, try switching to a window box for breeding. You will be amazed how well it works!

These are the most common reasons why radishes do not grow:

• the soil is too much fertilized - especially nitrogen promotes the formation of leaves
• you have sown the seeds too close
• you have sown the seeds too deep - cover them with maximum 2 cm of soil
• too little light and too hot. Radishes need a lot of light, but are not fans of the blazing midday sun
• the soil is too moist or too dry
• the earth is too solid
• Pests such as aphids or earth fleas are on the plants

Our conclusion

Grow radishes in the balcony box is not difficult and easily doable even for novice gardeners. With sunshine, enough water and lots of love, they thrive pretty much on their own. I wish you a good harvest and lots of fun watching the radishes grow!

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