Mold or mould on sprouts are usually root hairs.
Root hairs are fine, thin roots that grow from the thick main root of the sprout. The white fluff of root hair look like mold when the sprouts are young and they are a natural part of some sprouts.

Mouldy sprouts of radish FRESH SPROUTS


You can know root hair from mold by 5 characteristics:

Root hair is formed from 2-3 days. They are fine and white.
Root hair grows thicker as the sprout grows larger.
Your sprouts smell like a healthy plant. Not like wet soil.
Root hairs are only formed on the root itself – They are not formed on stem or leaves.
Root hair sticks to the root, and they break easily.

Root hairs are easiest for you to see when the sprouts are small. When the sprouts are older than 4 days, the roots look much more like ordinary roots. Root hairs are also most evident before you rinse the sprouts. This is due to the fact that the water causes the fine roots to cling to the main root.


It is just a selection of your sprouts that form the fine, dense roots that resemble mold. These are:

Broccoli · Radise · Pink kale · Rape  · Cabbage · Mustard · Sunflower · Grain (Barley, Wheat etc.)

All other sprouts form long, slender single roots. Those are roots without root hair. Sprouts with single roots are:

Fenugreek · Endive · Fennel · Lentil · Alfalfa · Clover · Mizuna · Mung bean · Rucola/Arugula · Pea

You can find all the seeds mentioned in the SPROUTS list.

Mouldy or moldy sprouts FRESH SPROUTS


Whether your sprouts form roots with or without root hairs has little to do with your cultivation of the plants. The root type is a part of the plants DNA and is all about pure survival for the plant.

Darwin and later scientists found that any species on this planet looks like it does because it is useful for the survival of that specific species. Only the strongest and best-fit plant survives to the stage where they form the next generation. So root hairs or not is quite simply basedon the plant’s strategy for survival.

The interesting thing is that plant roots do not grow randomly. They are always looking for moisture and nutrients the plant needs to form its leaf parts and to stay healthy. Plants with root hairs have the advantage that the roots can sift the soil close to the plant for moisture and nourishment and absorb everything. The disadvantage is that the plant is vulnerable to local drought due to its compact and often short roots.


As roots with root hairs is one strategy for a plant, roots without root hair – single roots – is simply another strategy. Both aim to ensure the best possible survival of the plant.

Plants that form single roots have the advantage that they can grow long, deep and fast. Only when the roots have reached a certain depth or encountered certain nutrients, the roots will develop side roots. Single roots are therefore as smart a strategy as root hair. It’s just another strategy. You cannot control the type of roots on your sprouts – that choice was made by Mother Nature long before the seed landed in your kitchen.

The beauty of growing your own sprouts is that the small plants get all the necessary nourishment from the seed itself. You only need to rinse the sprouts twice a day for them to get enough moisture and – voila – you have a nutritious, crisp, healthy sprout for your food.


If your sprouts form redheads or not, you cannot influence. It is the plant’s DNA that determines it.

On the other hand, you will notice that if you forget to rinse your sprouts morning and evening or it is very hot in your kitchen, sprouts with redheads will form a bit more root hair. The reaction to the lack of moisture lies in the plant’s genes, as the purpose of root hair is precisely to absorb all the moisture that is around the roots. If the plant therefore feels that it is dry, it reacts by “taking the chance” and forming even more root hairs.

Creating multiple root hairs is a chance. Because it also requires energy and nourishment of the seed to develop more roots. Therefore, if you want nutritious sprouts with root hairs, you should rinse so often that the roots stay nice white and crisp.

Moldy sprouts with fluffy root hairs FRESH SPROUTS
Mouldy sprouts with root hair in food FRESH SPROUTS


You can eat your whole sprout regardless of whether they have a single root or the wild root hairs. The roots are full of fiber and nourishment.

All roots typically have very little flavor. This makes it easy to use all roots in smoothies or in dips, if you do not find it optimal to use them whole in your salads etc.

The only important trick when you eat the roots is to rinse them clean as you do with the rest of the sprout. If you wish extra clean sprouts for your food, you can put the harvested sprouts in cold water mixed with lemon juice. Let the sprouts sit in this mixture for 10 minutes just before you use the sprouts in your dishes. The lemon will neutralize any bacteria that may reside between the dense roots. You can rinse the lemon away after the 10 minutes and your sprouts are completely clean.


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