You can buy corn gluten meal at feed stores. It's so disappointing that people are still using so many fungicides, herbicides and insecticides in their gardens when there are alternatives that don't impact the health of animals, insects and people. Believing claims that these things are not harmful to the earth is like believing tobacco companies who swore up and down for decades smoking wouldn't hurt you. STOP SPRAYING CHEMICALS IN YOUR YARD!! This may be unpopular, but I think those of us who are able to have a nice garden without killing/harming other living things have to speak up and say it's just not right. I also don't buy into the argument that it's easier for those of us with small yards to manage pests and weeds. I've taken care of an eight hectare property where no spraying was done -- and it was beautiful!! The impact these pollutants have spread far beyond your yard and collectively have devastating consequences.

I whole-heartedly recommend using Preen. A very small amount is effective and often you don't even need to reapply it! My lot is 80% garden and 20% lawn. I use no chemicals other then Preen, totally organic-- even the lawn food-- but I just had to make the exception for Preen. Yes, there are quite a number of perennials which reseed themselves, and as you observe your garden you'll figure out which ones these are. Foxgloves, hellebores, violets, Johnny Jump Up, melampodium (little yellow daisies), blanket flower (gaillardia), orange butterfly weed, and some coneflowers come to mind. So you sure asked the right question! You can just skip the areas immediately around these so they can reseed. That still leaves areas around the shrubs, azaleas, roses, ferns and other perennials; only treat the areas where there's a problem. I find edges of beds are the most important area to treat. Any area of the bed that borders on the lawn can easily be invaded if you have an organic lawn with lots of little "wildflowers" (e.g., weeds!). I rake back the mulch around those edges, apply Preen to the bare soil, water it in and replace the mulch. I could not garden at my age (70) without Preen. It saves so much time at home that I have time to maintain a huge organic rose garden at the zoo, PLUS two smaller rose gardens --one antique and one modern-- at the arboretum. Corn gluten is great for small patches of lawn or the vegetable garden where you don't want any chemicals but it does not remain effective very long. You really need 50# of the stuff; it is a component of livestock feed so you have to go to a feed store to get it. A side benefit of corn gluten is that it has a high nitrogen content and so it feeds the plants. I used it on my organic lawn back in Texas and it worked great. (It would work here too I just can't lift the bags anymore!) Bless you Babs for bringing up cardboard; that would work equally well with edges and the mulch will hide it. Lasts longer than newspaper and breaks down completely except for the scotch tape. I like to use cardboard under paths and between rows in the vegetable garden.

I do 15lbs/1000sqft of corn gluten meal and 15lbs/1000sqft dry molasses. Corn gluten meal is much cheaper than and the same product as Preen. I do this every spring and one more time before fall.

I fully endorse Sevin. I have found that my roses are happiest only when I use Sevin. My trees seem to take on a brilliant green glow with the use of Sevin. I feel that it's just the patriotic thing to do when I use Sevin. A product like Sevin needs no "scientific data" to prove its efficacy. It's just common sense that it works. For those that scoff at my endorsement, I would just like to say that it's my God given right to want the best for my roses. If you would prefer to tend to a garden of turmoil and watch your roses suffer as invasive terrorist terrorize your territory, that's all fine by me. I, on the other hand, use Sevin because it works. See, that right there is a satirical statement that one would make if one wanted to be a troll. The purpose of the commentary is clearly rhetorical and carries a slightly aggressive tone to enforce the message that I don't agree with previously stated commentary. Note the emphasis on "scientific data" to imply that scientific data is not an end-all when it comes to the basis of this argument. The point of this is to highlight what most people who frequent this site already know: 1.) The use or non use of chemicals is personal choice with equal consequences. Don't use chemicals and you have a full time job on your hands trying to address problems as they come. Do use chemicals and you eliminate beneficial insects as well as potentially affect the environment. 2.) 99% of the advice exchanged on this forum is anecdotal at best. This is not to say that none of the advice is valid. Unfortunately gardening science does not get the attention/funding that other higher demand areas get, leaving many to speculate on the best course to take in their gardens. There is a plethora of home spun advice that truly works and no one has an inkling of an idea on why it works. Eventually there will be empirical data to explain it all. For now we all take our chances and benefit from everyone's good will. 3.) Opinions are people's attempt at helping others see an angle that is possibly overlooked. No one, short of my previous example, purposefully puts out information with malice. Are some opinions more aligned with validity than others? Sure, but like that well intentioned fruit cake at Christmas, we accept it, smile, give thanks, and place it along side everything else we don't have use for in the trash. 4.) Data, specially scientific data, is a snap shot in time and space. We can all cite "evidence" where a well meaning scientist definitively concluded that one position on a claim was irrevocably true, only to have another, more in depth scientist debunk the previous claim. Look at the ever changing world of weightless and you'll note how true this is. This is not to say that everything is refutable. There are constants in our world, but the difficult questions rarely have simplistic answers. Be kind when you ask for evidence to support a claim. The data you suckle intelligence from could be a milk less teet, lol. Forgive my long winded words of fancy. I'm troubled sometimes with the lack of common respect that occurs between people of rivaling opinions and I feel I'd be in error if I didn't remind people what we already know. ;-)