It's been a lovely spring; the dogwood and azalea flowers held on longer than usual so there hasn't been the typical fifteen minute intermission between the first and second acts in the garden. Now the iris are blooming, the roses are covered with buds, the poppies ready to pop, and delphinium and foxglove spires gain a few more inches every day.

At least in theory this is what's happening. The end of May is Come to Jesus time for gardeners. I can no longer kid myself that the columbine might have reseeded itself, and that the special fern I got last summer is just slow to emerge. It's time to apply the cold eye of judgment and take stock of what's thriving and what's failing. The next step is to figure out why things aren't going well. Here are the most common culprits:

Shade- In our region many gardeners chase the sun. A sunny garden can become shady in less than five years as nearby trees grow up and out. If perennials like iris and Salvia and shrubs like roses aren't getting at least five hours of sun every day, they will become weaker over time, give poor flower performance, and be more susceptible to disease. Rearranging these plants in a sunnier spot (cheap) or trimming and/or thinning trees (expensive) will bring a sunny garden back to vigor.

Plant selection- before you blame yourself for not being a good gardener, do a background check on the plants that aren't doing well. Certain plants are magnets for disease and can be very difficult to grow in our climate. Hollyhocks get rust in about two seconds, and some varieties of zinnia, phlox, and bee balm are very prone to mildew. The biggest dog has to be the hybrid tea rose, which is virtually impossible to grow under regular garden conditions. If you suspect you have plants in this category, throw them in the trash (don't compost.)

Soil- This is the biggest factor in plant success, and the most variable. Good gardeners are mostly good soil engineers, and understand that most plants like soil that is fertile and well oxygenated. Ideally, there shouldn't be any bare earth in a garden. Without a covering of plants, compost, or mulch, soil loses its nutrients and also becomes compacted by raindrops, surprisingly enough. If you've recently had construction, tilled your garden, or had major tree work done, your soil is also probably compacted. Applying gypsum, a naturally occurring mineral, will loosen compacted soil if it's done annually for three years. And although plants will be slower to establish in compacted soil, eventually the roots will break through the compaction and allow much-needed air and water space between soil particles.

Also, soil will become depleted over time, so organic matter should continually be reintroduced. Once mostly composted, leaves and household plant waste can be added back to the garden; no need to dig it in, just spread it around the plants. Heavy feeding plants will benefit from applications of organic fertilizer. And (my opinion here) all plants do better with the addition of some kind of animal manure. The cheapest and least smelly is dehydrated chicken manure, which can be applied a few times in the growing season. By adding compost and manure, I've greatly improved the terrible soil in my garden over the past two years, and it's looking much better.

Although there are hundreds of other reasons plants can languish, these are the most common. And the good news is that all these problems can be fixed relatively quickly, so you can get your garden on!