The weather has really been hard to plan on this year. We are finally getting some rain and cooler temps. Another idea for planting iris rhizomes is to plant close together and use shade cloth and water them. Then you can move them later when it cools down a bit.

If you are using preen (or any other brand of preemergent herbicide), plant the iris first, then sprinkle the herbicide. If you plant afterwards, you are disturbing the soil and potentially unearthing weed seeds. The chemical is extended-release, but since you have a choice, planting first gives you the best results.
In a perfect world, the bed is planted and completely weeded or hoed in the spring, and preen applied then before weeds really get started. The bed is then left undisturbed for the season. But...we all add more plants, and that brings up new seeds. If you are planting seeds in a bed, wait until the seedlings are up and have real leaves before applying the Preen. Of course by then, you'll have weeds springing up and you'll have to weed very carefully.
I have a friend who sprays Roundup right over the iris bed in the summer well after the iris have bloomed. The iris are resting at that stage and are pretty much unaffected, and the weeds are killed. He doesn't have plants other than iris in that bed. My beds are mixed, so I haven't tried using Roundup. It works for him, though, and it's cheaper and faster than Preen or Snapshot.
We didn't have much of a winter here this year, and some of the weeds never died down. The Preen lasts about 3 months, (less than that in extreme heat) but our growing season is long enough I have to use it twice. Snapshot is expensive, but it lasts so much longer that it's worth it. The heat has been so horrendous that many of the weeds have died off! It was over 100 every day in July, with only .13 (yes you read that right, just over one-tenth of an inch) of rain for the month. My iris are now putting up new fans, even without rain or irrigation. What troupers!
The forecast is for temps of 106-108 for the next 10 days, so I hope none of my orders arrive for at least another 2 weeks.

Thanks Cindy, that helps. The weeds have been slow to germinate this year as dry as it was, but now after a couple of rains they are making up for their lost time.
Mary Ann, I have a few more veggie garden pics in a thread in the vegetable section if you'd like to see some Artichokes, tomatoes and peppers. I don't have a really big garden anymore, just me to feed, and I don't need to feed half the county like I used to. lol I am experimenting with growing artichokes here in Wis. and I have my first bloom coming!

Tom, why not put Preen down now, and then as Cindy says sprinkle some around after you're done planting and have disturbed the soil.

I've used Preen for many, many years, doesn't hurt anything.

Nice huge bed, it will surely be gorgeous.

And nice veggie garden. Any hot peppers in there?

Oh yah, some hot ones and some mild ones, Gotta have my salsa.

We just made salsa, yummy. Best chips I've found to go with it comes from Chiles, the restaurant. I don't eat there, just buy the chips.

One year I had a huge ton of hot peppers left in the garden. Frost was predicted, so I ran out and got them all, cut them up to freeze them. I did use gloves for the hottest ones. All of a sudden I started shaking, and it felt like my whole body was on fire. Just hot pepper overload. i was OK the next day.

You should make your own tortilla chips, not that hard to do, and man are they good.

I have, and yes, they are. But in a pinch Chiles are great. Ever tried them?

I've been battling weeds because I've been afraid to use Preen until I know I won't be planting any irises or daylilies for three months -- which means I can't use it in the late summer/fall when I'm planting -- but am I worried needlessly? I thought the Preen would inhibit the iris roots from growing/developing. Ideally I would use Preen three times a year, but I've not used it in the fall/winter/spring because of worries about plant growth. Please let me know if my fears are unfounded, because I have a bunch of weeds out there right now and would love to use Preen again but felt I couldn't because in Sept. I'll start planting again.

You are needlessly worried. Remember it won't take care of existing weeds, though, only the seeds sprouting.

I promise you. I've been using it so many years it will hurt nothing but inhibit seeds from sprouting.

If you're still cautious try it on a small area, and you will see.

I use Free hand for pre emergement as it does broadleaf and grasses, I dig the fields, put compost down replant and then water and then before the end of Sept or first part of October I put down Freehand, Never inhibited their growth in the least. I also fertilize at this time. So when they are going into the winter they have food and pre emergement going into the the dormant time. Hope this helps.

D

The following is a quote taken from an e-mail that I got from Paul Black when I asked him what they do to prevent weeds.

"We alternate two products, Ronstar and Snapshot. We use them after we work the beds and have the irises replanted. We dig and replant almost everything, every year. Don't incorporate it into the soil before planting. It will inhibit root growth. Treflan is one of the most potent. I don't use it. It tends to inhibit root growth whereas the others don't when used properly. Most of them come granular and liquid. Be sure to read and follow label directions."

I'm not sure if the active ingredient in Preen is the same as these two or not. I haven't been able to locate a sourse for either product mentioned locally, so I haven't tried it.

If you go to a farm store that sells to the farmers you should find all the products. I use Freehand and Ronstar, as since using Freehand I find it better

D

John read the label on Preen & took it back to the store. So we use 'hands' but they we are not a commercial garden.

Dee --if everything had the root system of 'Dapper' life would be great.

Wouldn't it.

D