I have two pots of 4 nasturtium plants each on a deck in full sun. When I first got them (in early June) they were quite happy, but lately they are not thriving. Each pot contains an Empress of India, Jewel mix, and two other plants of unknown cultivar (purchased at a farmer's market). All of them were purchased as seedlings. Initially they got happier after I planted them in pots, but then there was a decline.
I'm in zone 5a, western Maine near the mountains. It has been an average to cool summer (highs varying from upper 60s to low 80s, lows in the mid-50s to mid-60s) though unusually wet. A couple of times for real downpours I hauled those giant pots into the porch because I feared the nasturtiums were getting too wet. So are they too wet? Too dry?? The leaves have been yellowing and some have been drying to brown and dying. So that makes me think the plant might have been too dry or the soil too well-drained? They also get a ton of sun, and the dark blue pots get quite hot, so I've been wondering if they're just cooking and frying in too much sun also.
I know nasturtium favor poor soil, so they are planted in poor and very well drained soil, lots of sand at the bottom. Is the soil possibly *too* poor? I'm stumped! Thanks for any help. They bring the hummingbirds so I especially love them!
(I do dead-head them, but haven't done so in the past two days so pardon the dead blossoms.)
