There is a general 'rule of thumb' with transplanting or dividing perennials - Spring bloomers should be moved in the fall, Fall bloomers in the spring. But this is not a hard and fast rule, as I have moved Peonies in the Spring! They didn't like it and sulked for the entire season, but they were fine in the long run. The best weather for transplanting are the cool and drizzly days kinda like today - you don't have to worry about the roots drying out at all, and the rain helps the plant settle in. It is a very messy activity when it's wet, I guess it's like playing in the mud when you were a kid! This Spring so far, I have moved 2 large shrubs, some smaller ones, a whole mass of Hostas, and a bunch of bulbs. Most of these were near the house, so the soil was "warmed up" and very workable. I haven't plunged headlong into transplanting anything out in the garden beds yet, but very soon. Sounds like this week's going to warm up, so it should be no problem to get going on this. As for seeds, cool season plants can be sown now - Poppies, Fennel, cool season veggies, etc. I would wait until after the last frost to direct sow warm season seeds.

Never mind, found someone to answer on the Perennial Forum. Looks like this place isnt visited much.

Susan: Sorry to hear of your problem. You can use a product which is organic (not a chemical pesticide). It is sold under several names locally. See if you can find this Thuricide or BT (Bacillus Thuringiensis var kurstaki) it only targets what it is sprayed on will not hurt good insects like lady bugs, praying mantis, etc.. washes off and has no long term activity.So as not to harm your butterfly larva. As to were your to put your B&B plant is leave it there or move it but the moth larva will still find it.Eliminate the moth larva and they should not come back. I have not had this problem with my B&B but onther problems. I almost forgot it does not act like a poision (because it is not one) the larva will still be there for a short time but they will stop eating and then die.

Just to add to what emmarene said...the way I work and I think many designers do is to have a plan but there has to be flexibility. There are many plants that can be found at the nursery pretty much all the time, but some plants may not be available or be low quality. Or some times there's s specimen plant that's just too good to pass up and I'll modify the plant list right on the spot. I personally would never allow the client to buy the plants...that's just asking for trouble. If half the plants die I'm likely to be blamed by the client. The only way I might this is if I'm just doing the design and not the install. If you hire someone let them do their job. Otherwise you're just wasting money. And how much money are you saving? I buy my plants at a wholesale nursery. Way better selection of plants and sizes. I often pay less than even Home Depot. Like right now 1gal Lantana is $10 at MD and $8 wholesale. So how much do you think I'm going to knock off the bid if you provide the plants? $8? $10? Something like that to make you happy. I'm also going increase the overall bid 10-20%. I have to assume the plants the client buys is going cause problems. I'll have to spend a lot of time walking the client thru the process and when time for the install comes there are going to be missing plants, dying plants, the wrong plants, wrong sizes. For those types of clients I'm more than happy to lose the job. Heck, I'm never going to get the job anyways because they're looking for the lowest price and that's it. There's always going to someone on Craig's List offering a lower price because they don't know what they're doing or they're really good at ripping people off. Ripping off people looking for cheap is pretty easy and very common.