Flower Grenades Gardening's gone guerilla - you've seen them, you may have looked away, but you've seen them. Those forgotten areas of the estate, left to fall apart and fall into disrepair. The municipal scrubland where nothing can grow... Or can it? turn the concrete jungle into a wilderness with our compacted wild flower seed grenades. Buttercups and poppies will take at least 3 weeks to start growing ryegrass will be the first thing to grow after about one week The flower grenades are clay grenades filled with growing medium and wild flower seed (ryegrass, poppies and buttercups) Each grenade measures approx 7 cm x 10 cm x 6 cm Great garden gifts for any wildlife lover or young gardener!