|I like to plant vegetables but pests eat on the fruits - mostly slugs snails. My roses have black spot. I want to use only organic pestsides.|
|If the feeding is at night, you might suspect snails, slugs and earwigs. In most gardens there's a balance of beneficial insects and destructive insects. Once a population of bad guys gets established, a crew of good guys usually shows up. Since you're growing organically, you'll probably want the insects to battle it out, with the good guys gaining control. You can encourage beneficials by having something in bloom at all times, and by avoiding the use of pesticides (which will kill good guys as well as bad guys). Even organic (botanically derived) pesticides can harm beneficial insects and should be used only as a last resort. Most pesticides are pest specific, so it's important to positively identify the destructive insects and use a product that targets them and them alone. At this point I'd try to identify the damaging insects. Go out after dark with a flashlight and see if you can determine what's causing the damage. I suspect, if the feeding is at night, that you're dealing with slugs, snails and/or earwigs. You can trap these critters by providing a dark, damp hiding place. Try an upturned terra cotta pot in the garden, propped up with a small stone. The pests will hide inside during the day and you can empty the pot each morning and replace it in the garden. You can also try dampened, rolled up newspaper traps in the garden to lure the bad guys. Simply toss the papers in the garbage each morning and place new traps out in the late afternoon. Hope these approaches help you control the pests in your garden!
As for the black spot on your roses, there are fungicides you can purchase to help prevent the problems, but some roses are more susceptible to black spot than others. Try to avoid the disease by making sure your roses are getting 8 hours of sunshine a day and that there is good air circulation all around. Keep water off the foliage and prune off any leaves that you suspect are developing black spots.
Best wishes with your garden!