These soil blocks are great if you are new to gardening and want to see if you like planting your own seeds without purchasing anything but your seeds, Allows you to plant 180 seedlings in a 12x16 inch tray and keeps seedlings from becoming root bound. Go to our blog "Growing seedlings with premade soil blocks" to see how it is done. It is best to use them as soon as you can. So order these close to the time you will plant your seeds. We make them up just before you pick them up. No shipping on this product.