Biologist Warns of the Dangers of Too Many Seedlings on the Windowsill

Growing seedlings at home is not inherently dangerous to health; however, if there are too many plants, and the room is poorly ventilated or they are improperly cared for, certain risks may arise, said biologist Maxim Larionov.

“With abundant watering, high humidity, and poor ventilation, mold often develops on the surface of the soil. Its spores can enter the air and cause discomfort for people with allergies, bronchial asthma, or chronic respiratory diseases,” he warned.

Another factor is increased humidity in the air. If the entire apartment is filled with containers of seedlings, regular watering is conducted, and mini-greenhouses or plastic coverings are used, the humidity in the room can significantly increase. This creates favorable conditions for mold growth on walls, windowsills, and window slopes.

“Some plants release a considerable amount of pollen or have a pronounced fragrance. During flowering, this can provoke allergic reactions. However, most vegetable crops are planted in open ground long before flowering, so this risk occurs much less frequently,” the expert noted.

If a low-quality soil mix or soil collected independently without prior treatment is used, it may contain fungal spores, bacteria, insect eggs, or pest larvae. It is better to use ready-made substrates from reputable manufacturers or to pre-sterilize the soil.

“Do not forget about plant protection products. Sometimes owners start using insecticides, fungicides, or growth stimulators right in the apartment. If the instructions are violated or ventilation is lacking, chemical preparations can irritate mucous membranes and respiratory tracts,” he advised.

There is also a less obvious problem — additional artificial lighting. Phytolamps are necessary for the normal development of seedlings, but if installed incorrectly, they can create discomfort for the eyes, disrupt sleep and rest patterns, especially if they operate late in the evening or at night in a living room.

“At the same time, the widespread myth that a large number of houseplants or seedlings ‘take away oxygen’ at night and make the air dangerous has no scientific confirmation. The amount of oxygen consumed by plants at night is negligible compared to the air exchange in a typical living space and does not pose a threat to humans,” he concluded.