leeks

If it still has its roots it should recover if you water it in well.

As for feeding, if they've not had anything since they were planted they may well be hungry; at this time of year I'd probably give them a liquid feed as there isn't that much growing time left (despite the current heatwave!)

not ideal as it may encourage them to flower.........but if that's all you have, then use it

any liquid feed for veg..wilkinsons sell one for about a £1