Slow Release Plant feeders

I bought 5 slow release plant feeders 5 in a pack from the �£1 store, It said snip the end off and put them in your containers, they are drip feeders last 30 days, did what it said checked 2 days later and the whole lot has gone.
I wont be buying them again mind didnt mind seeing that they only cost a �£1, when i saw them thought it was a great idea at the time

 

Don't write off the pound shops, if you look there are plenty of bargains