Background:

So I'm relatively new at gardening. My family has always been heavily into it both in vegetables and flowers (hence, the next generation), and I always hated the slimy things in the dirt and had no interest - you'd swear I was adopted if I didn't look like them. Well 3 years ago I started to spend more time with my fiance at his house. He bought it from his family after his grandmother had been moved into a nursing home in her 90s. And since he has a serious aversion to weeds, he covered everything except a few of the larger plants with weed barrier and put stone on top. That was a few years before I met him. By that time, his daylilies were being choked to death by years of dead foliage, the rest of the plants were dead, and he had a serious slug infestation thanks to all the moist decaying plant life on those lilies...I am STILL waging war against the little buggers every year...

So that's where I came in. I figured the poor plants should at least be rescued, and that the seriously spartan house on the block could look quite charming with a few additional plants making it look lived in. So I bought a couple things that looked cute at Lowes and Home Depot and put them in the ground. Sure enough, the neighbors all stopped by to say how wonderful things looked and how pleased they were that this poor house wasn't vacant anymore... yup... they thought it was vacant... the fiance isn't a social butterfly and the driveway is in the back of the house so... yeah...

Well my intervention turned addictive... I kept adding things, looking at more options, and I've been off and running ever since. I even got the VERY nice surprise that after I took care of the garden, some of his grandmother's plants HAD survived in dormancy and came up the next year. The stella d'oros that were being choked out have more than tripled in size - I had to give some clumps away and will be thinning again this year.

Dilema:

I haven't a clue as to how to landscape and the best advice I can get out of my master gardener mother is "it's just trial and error." Well the stone is still there in the gardening beds because they're right up against the house and my fiance fears termites (legitimate though I'd prefer Rubber mulch I think or at least stone that isn't sharp) and it hurts my hands every time I put something in...even with gloves... so I'd like to avoid the trial and error route for that reason alone, but it's also not ideal to send my hard work into transplant shock 10 times until I get it right.

Right now, I have a linear pattern. I have about 2 1/2 feet in depth to work with, but while I interspersed the plants down the line, I have blank spots to the front and back of the plants. The flowerbed surrounds the house so the one I'm having trouble with is the entire length of the side.

I have two heliopsis which were 5 feet tall their 2nd year... I have 2 russian sage that are interspersed well, and stella d'oro daylilies which I did leave in their spaced out 3 clumps. I have at least one delphinium which went about 4 - 4 1/2 feet tall in its second year, but I'm not sure how the other ones I planted will do, if they come back... I wasn't happy with the plant supplier. I don't think the heliopsis can even be moved safely because of its size... it seems VERY happy where it is.

So does anyone have any suggestions for good plants to go with what I have that won't need a ton of space? The entire flowerbed is Full Sun with the back third getting a little more shade toward the end of the day than the rest but it's still plenty sunny.

Most importantly does anyone have suggestions about how to arrange what I do have and whatever additional plants I might buy to go with what I have to create a more cohesive flowerbed?

I am looking to stay with perennials as I don't want to have to redo that flowerbed once I get it done. I have another flowerbed I put in that I can use to play around with annuals - and that one wasn't done in stone :-).