Why is there rust in my pots?
Q
Some ‘rust’ has appeared on the compost of the fuchsia and begonia cuttings in my greenhouse. Should I be worried? Pauline Kingsley (via email)
A
This is quite likely to occur in plastic pots, too, but it may be exacerbated in the cardboard pots as the moisture will travel slightly differently and the compost will drain differently.
It isn’t really anything to worry about, but if it appears to be affecting the growth of your plants then it is a wise move to put the plants in different pots. It is also worth watering the compost from overhead and ensuring it drains properly, so the
compost doesn’t sit too wet.
You might also increase ventilation in the greenhouse so there is good air movement across the surface of the compost, helping to improve drainage and moisture levels. You probably won’t get rid of the deposits completely where they formed, but if you lightly push them back into the surface of the compost before watering overhead they will become less visible.