Thanks for the words of encouragement on the state of my flower bed :)

I hopped outside to get a quick pic of the gardenia. I have one on the opposite side of my front step and it seems to be doing fine. This one is looking quite sad though!

If you give the Gardenia Miracle Grow be sure that it is the one for acid loving plants. Both of the Gardenias will like that. The bed looks great! It seems to be pretty full as it is. You are going to be a wonderful gardener!

I think your beds look great! I've been gardening extensively for 30 years and believe me, not everything works out like you plan. No matter what the label says or what you read on the interweb about a particular plant's characteristics, what they do in your own yard is up to the plant! Experience, trial and error, expensive mistakes (lol) will all teach a great deal. The experts in landscaping design will always tell you to have a PLAN and stick with it, to the extent you can. Don't go crazy in the nursery and buy a bunch of stuff that isn't part of the plan. A confession: I try to have small micro plans such as pairing the right colors together, sizes and water requirements but I completely go nuts in nurseries and continually have plants in pots waiting for a permanent home. Don't be me, lol.

If you have perennials that are not in the right spot, just move them in the fall. And if your gardenia doesn't recover, just get another! Sometimes you simply have a weak specimen.

I love your garden, it has so much color and life! I don't see room for another plant in there though.

I have no idea on the gardenia, I've always heard that they are really difficult here so tried once, failed and never planted them again.

How is the gardenia? Any change? I agree with using the miracle grow for acid loving plants (MirAcid I think it is called). We have a hedge of gardenias in front of our house (north side). It seems pretty bullet proof. A little mildew in the winter on the leaves but no major issues.

Gardenias need humus-rich, acid soil. In fact, planting next to a concrete foundation can be too much exposure to alkalinity. Remember that your water may be alkaline, and over time that will affect the pH of the potting mix. This may be the cause of the chlorosis.

They also need full sun, but protection from heat. Your current location will have a lot of reflected heat from the brick and walkway. Make sure plants are adequately watered if there is no rain, especially during bud formation.

Also, make sure you did not plant this gardenia too deeply. The roots should be at the top of the soil and any mulch should be away from the stem to avoid fungal disease. As plants lose soil through drainage holes some nurseries refill the top of the pot. If the soil top in the pot is planted at the garden soil level, the plant stem is then too deep.

Thanks for all of the feedback everyone! I decided to leave the flower bed as-is since it received so many compliments :)

The gardenia keeps looking worse and worse unfortunately. I had already worried that it wouldn't fare well once the summer heat kicked in, so I'm thinking about taking this as an opportunity to pull them up and replace them with something a bit easier to maintain.

Does anyone have any recommendation for a fragrant flower that can rival gardenia's intoxicating perfume? :o

If you want to keep that container where it is, consider Lavander. It prefers hot summers and well-drained, neutral to alkaline soil.

Chocolate Daisy (Berlandiera lyrata) has chocolate-scented yellow flowers from summer into fall and is hardy in zones 7 to 9. Bouncing Bet (Saponaria officinalis) is an old-fashion, fragrant perennial with white, pink or red flowers and is hardy in zones 3 to 9.

Heliotrope is a tropical perennial with purple to white blooms. Tuberose is a tropical bulb with white flower spikes in late summer. Mignonette is an annual with small, very fragrant flowers that vary from white to yellow-green to greenish.

Most shrubs get too large for your container, but Sweet Box (Sarcococca hookeriana) only gets 3 ft tall and wide. Its blooms have a heady fragrance in late winter. It's hardy in zones 8 & 9 with the variety humilis hardy to zone 7. It's evergreen but needs shade to part shade.

Possibly white butterfly ginger?

If you’ve ever appreciated the smell of a gardenia, Butterfly ginger is at least that fragrant if not more.....

Some perennial flowers may meet their full height description after a few years. But I've found that to be a problem, too, sometimes because if they are being shaded out by plants in front, then they don't reach their full potential, even after several years.

As for what others have said, the initial landscape may have everything in place and order, but as subsequent years come, the plants will live and thrive in various ways that may not have been what you wanted but will still be pretty good.