Go to your local craigslist.org and search for "perennials". You'll probably find a LOT of local gardeners (professional nurseries to people that are just in time for splitting their perennials) selling huge clumps of perennials for dirt cheap. Because they grow locally and they're fresh (some will say "bring your own shovel and containers) they will be a good choice for your garden.

Usually the prices range from $1-$5 a clump depending on how rare they are or how fast they multiply. Still much cheaper than any store. Plus you KNOW that they do well in your area, and you can see with your own eyes what kind of habitat they like best.

So, search for perennials on craigslist and Google the results to see how tall they grow, what kinds of conditions they like, etc. It's your best bet. Even cheaper and more reliable than free trades over the internet (shipping costs add up quickly!).

It is almost impossible to have bloom all season from perennials, especially in a bed as small as you describe and with the height limitations you describe. Experienced gardeners know that garden interest actually comes from foliage color and texture and contrast in plant shapes. Flowers are then a bonus. Start looking at plants with great foliage and work from there.

I agree, planning a perennial bed for all season interest is a full time job. Foliage plants and small shrubs are very helpful.

I am your neighbor. These plants do well in full sun and stay low for me:
bulbs (daffodils, species tulips, crocus, hyacinths, etc.), some campanula, some heuchera, dwarf shasta daisy, dwarf iris, perennial geraniums, dwarf daylilies and lilies, groundcovers (Creeping Jenny, ajuga).

I love low growing colorful shrubs: Spirea 'Golden Elf' and Weigela 'Midnight Wine'. Weigela 'My Monet' is beautiful, but it is struggling in my garden. These shrubs add color and structure to perennial beds and they are virtually care free.

It takes a lot of research and planning to plant a nice looking perennial bed.

Thanks for the suggestions all. Alina - you mention some plants that I'm interested in but how do I deal with spacing? For example, crocus will come in very early, something like shasta daylilies will come in later. Do I plant those nearly on top of each other if I want a particular plant to take over when when one fades? Or do you spread things out - leaving holes when something like a crocus goes dormant?

Bob

Bob,
Spacing depends on the size of the mature plants (google for the plants of your choice) and on your personal preference. My beds are stuffed with plants, but I am going to reduce the amount of plants on my front yard beds for a more formal/less cottage look. It is really hard to plan with plants that loose their foliage. You will have to hide fading foliage among later growing or lush plants. Again, that involves a lot of research. That is why laceyvail gave you a great advice to go with foliage plants and shrubs first. It is much easier to plan with them. You can add blooming perennials then. Be prepared to move things around to achieve the look you want. Nobody will give you a perfect recipe for the entire bed (I already said - it is a full time job!), but you can get a good advice here for particular plants or combos.

As for crocus, I plant it directly on my lawn. By the time the grass starts to grow, crocus is done.

Here are plants approximately in your size specs that bloom well for me here in east Central Mississippi. I have started keeping a garden journal this year, so I will list them in their order of bloom up to today. I have had something in bloom continually since the first week of February, if you count the bulbs. The ones with a * bloom for more than a month. The ones with ** bloom even longer.
I also include a few first choice shrubs. Without them your border will be utterly empty in the winter.

Daffodils (since February)
Summer snowflakes (bloomed in late February)

March:
tulips

April:
Loropetalum, Purple Pixie (Dwarf, evergreen, purple leaved shrub with hot pink blooms. 3' x 3')
**Snowflurry verbena
Coral Bells Azaleas (evergreen shrub, cotton candy pink blooms, 3' x 3')
Camassia (bulb)
Amsonia tabernaemontana (blue blooms, grey-blue foliage. Looks like a shrub in the summer border, though dies to ground in winter. Gets about 2' x 3')
**Nearly Wild roses (2.5 x 3')
**Carefree Sunshine roses (3'x3')
*Penstemon tenuis
snapdragons (annuals)
Gladiolus Byzantinas, Cruentas (bulb)
**Heliotrope, Azure Skies (part of the Southern Living Plant Collection. Blooms spring to frost)
**Encore azaleas (blooms lightly in spring, then Aug - Nov.)
Spanish Bluebells (bulb)
Dianthus, Firewitch
Golden veronica (Trehane, I think.)
**Rozanne geranium (till frost)

May:
Dwarf Nandina, Harbour Belle (evergreen, 2'x3')
**White Out hydrangea (3'x3'. Repeats in flushes)
Shasta daisies (height depends on variety)
Blue Love grass (eragrostis)
amaryllis (bulb)
**Crinums (bulbs)(in flushes from May till frost)
*daylilies (six weeks or so with enough varieties)
**Kalimeris Blue Star (till frost)
**Salvia, Mystic Spires (half hardy. Blooms till frost)
**Salvia farinacea, Veronica and Rhea (half-hardy. blooms till frost)

Still to come:
**Peachie's Pick Stokesia (any day now. Blooms in flushes through summer with deadheading)
**zephyranthes candida (evergreen bulbs. Blooms in flushes from July to frost)
Purple muhly grass (blooms in fall)

I have grown everything on this list for more than two years. They are every one easy, low care, and beautiful. I grow organically.

Some things I've learned with starting with perennials in a bed:
#1 No matter how hard you try to work it so that things bloom in succession, it NEVER seems to happen that way in reality!

#2 You will keep moving things around as it's never quite right!

#3 Some of the perennials will NOT look like what you quite expected or grow to the heights or widths expected!

#4 Some of them will not survive the winter and you'll end up replacing them!

#5 Some of them may get diseases and fail, some will thrive, and some will just do ok.

#6 The colors never look quite like you'd expect for the most part.

#7 When it all comes down to it, it is always a work in progress!

#8 Have fun, it's a rewarding challenge!

Great guide Donna! I am afraid that most of the plants you mentioned exceed Bob's height limitation.

Bob, to give you an idea of combining shrubs, foliage plants, and perennials, here are some of my beds (still in working progress, my garden is less than 3 years old):

Rose Double Knockout, irises, Crape Myrtle, etc.

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On the right side of the gazebo (sunny spot, almost full sun): Peony, heuchera, Creeping Jenny, Clematis (background, on the trellis), weigela Wine and Roses and dwarf Midnight wine, dwarf Crape Myrtle, sambucus Black Lace, Irises.

{{gwi:220374}}

Beds with more shade: Hosta, Hydrangea, Heuchera, Brunnera, Peonies, etc.

{{gwi:238606}}

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The same bed at different time:

{{gwi:238608}}

and

{{gwi:215905}}

I keep experimenting and moving things around :)

Alina - thanks for the pictures - beautiful beds, you have a great touch!

Thanks Bob, they are still in working progress. I do have some favorite combo that I am going to keep.

Good luck with your project!