Pocket BotanistThe spider plant (Chlorophytum comosum) is famous for being unkillable, and nearly as famous for brown leaf tips. Almost every spider plant in a home has a few. They are not a sign the plant is dying, and they have a short list of causes, most of which come down to what is in the water and how often it arrives.
1. Fluoride and chlorine in tap water
Spider plants are among the houseplants most sensitive to fluoride, which is added to tap water in many areas and which the plant accumulates in the leaf tips, the end of the line for the water it transports. The pattern: tips browning evenly across the plant, on old and new leaves alike, in a home where the plant is otherwise well cared for. Dracaenas and peace lilies do the same.
What to do: water with rainwater, filtered water, or tap water left standing overnight (which loses chlorine but not fluoride). Distilled water works but carries no minerals, so alternate it with tap. The existing tips stay brown; the new leaves come in clean.
2. Fertilizer salts
Too much feed, or the slow build-up from years of tap water, leaves salts in the soil that burn the roots and show at the leaf tips first. The pattern: brown tips plus a white crust on the soil surface or the rim of the pot, often on a plant that gets fed regularly. What to do: flush the pot by running several pots' worth of water through it, then feed at half strength once a month in summer and not at all in winter. Spider plants need very little.
3. Drying out too hard
The thick white roots store water, which is why the plant survives neglect, but a pot that goes bone dry for a week loses the leaf tips every time. The pattern: brown tips after a holiday or a heat wave, with the leaves paler and a little limp. What to do: water when the top 2 to 3 cm of soil is dry, not when the whole pot is. In summer that may be twice a week for a plant in a small pot. A root-bound spider plant dries out fastest of all; if the roots have pushed the plant up out of the pot, repot into one a size larger.
4. Dry air and direct sun
Winter heating drops indoor humidity to desert levels, and the tips of thin leaves dry out first. A spider plant in direct summer sun through glass gets scorched patches as well as brown tips. What to do: move it out of direct sun to bright, indirect light, and away from radiators. Grouping plants together or using a humidifier raises the humidity around the leaves. Misting makes little difference and is not worth the effort.
Trimming the brown tips
Brown tissue does not recover, so trimming is cosmetic, and fine. Use clean, sharp scissors and cut at an angle that follows the natural point of the leaf, leaving a thin margin of brown rather than cutting into green, which just makes a new brown edge. If a leaf is more than half brown, remove it at the base. The plant replaces leaves quickly.
The babies are the tell
A spider plant that is producing plantlets on long stems is a happy spider plant, brown tips or not. If it has stopped producing them, or the new leaves are coming in with brown tips already, then the cause is active and the water is the first thing to change. Once the plantlets have a few roots of their own, they can be potted up as new plants, which is the whole point of owning one.
A reminder tuned to the pot
Pocket Botanist sets a watering reminder for a saved spider plant from its pot size, material and the light where it lives, and the reminder shortens in a heat wave and lengthens in winter. Free on iPhone and Android.
Sources
- ASPCA, "Toxic and Non-Toxic Plants: Spider Plant." aspca.org
- Royal Horticultural Society, "Houseplants: growing and care." rhs.org.uk