Companion planting indoors

A mix of both, honestly. Some pairings have real, measurable benefits, like basil's scent deterring certain pests near tomatoes, while others are traditional lore with little hard evidence. Indoors, the most reliable benefit is practical: grouping plants with the same light and water needs so they thrive in one pot. Treat the pest-repelling claims as a bonus, not a guarantee.

Group by what they want, not just what folklore pairs. Mediterranean herbs like rosemary, thyme, and oregano all like dry, sunny conditions and share a pot happily. Basil and parsley prefer more moisture, so they go together. The mistake is potting a thirsty plant with a drought-lover, since one always suffers. Matching needs matters more than any traditional pairing.

Mint, above all, keep it solo. Mint is aggressively invasive and will choke out anything sharing its pot, swamping the roots within weeks. Fennel is another poor neighbour that inhibits nearby growth. Beyond those, the main clashes indoors come from mismatched water needs rather than chemical hostility, so separate the soggy-lovers from the dry-lovers.

A little, mainly through scent-masking, but do not expect miracles. Aromatic herbs like basil and chives can make it harder for some pests to home in on a target plant, which helps. Indoors, though, you have fewer pests to begin with, so the effect is modest. Good airflow, not overwatering, and inspecting leaves do more for indoor pest control than companion planting alone.

Yes, and that is its best indoor selling point. Combining compatible plants in one well-chosen pot makes far better use of a small windowsill than scattering single pots everywhere. A trough of mixed Mediterranean herbs gives you four or five crops in the footprint of one. Just leave enough room for each to grow without the strongest one crowding out the rest.