All of us enjoy growing flowers, especially perennials. The wonderful variety of colors that we see in our and our neighbor's gardens are such a joy.
Obviously we first need to make clear what we mean by perennials. We must differentiate them from annuals and biennials. Annuals, of course, are only with us for a single year or part of a year. Most of them survive for a good part of the spring and summer. Some of my favorite annuals are petunias, cleome, cosmos and impatiens. Biennials are plants that, although they put up foliage each year, they tend to flower in every other year. These include most types of hollyhocks and foxgloves.
Perennials, on the other hand, are with us year after year. We plant them once and the biggest problem we have thereafter is controlling their expansion. It is always a good strategy to check the tag closely to see how big the plant is expected to get. We'll look at some perennials further along. Perennials are also seasonal. Few of them flower all spring, summer and fall, so consider the season of time of bloom as well.
In spring we have crocuses, candytuft, moss phlox, tulips, daffodils, columbines, allium, heuchera and my very favorite early bloomer: hellebores. As summer comes on we early see all types of irises, peonies, astilbes, dianthus, daylilies, garden phlox, yarrow, gaillardia, coneflowers, gladioli, cannas and many, many others.
In the fall we get sedum, colorful ornamental grasses, chrysanthemums, asters, Joe-Pye weed, goldenrod, nepeta and many more.
Now for a few specifics: It seems that the most popular perennial in Rhode Island is the hydrangea. They come in many different species actually: lace-caps, oak-leaf, mopheads and peegees are some of the most popular. They are relatively easy to grow, but they require very careful pruning each year. Both 2011 and 2012 have been outstanding hydrangea years in Rhode Island. Much advice is given about how to properly prune hydrangeas. First of all, in the fall, it is okay to cut off the dead flowers very carefully. Do this individually and not with hedge-clippers. What works for me is primarily to leave the hydrangeas alone until very late May or early June. I know they look like dead sticks with a few leaves on them by that time. But this enables you to see what is leafing out and you can even remove a few dead canes from the center without cutting them. Do not, under any circumstances, cut hydrangeas to the ground: EVER! If you do so, you will have NO FLOWERS that year and possibly the next year as well. I would strongly recommend if you grow hydrangeas that you check out an excellent website. It is www.hydrangeashydrangeas.com. There you will find an encyclopedia of hydrangea information species and how to care for them. Most gardeners want to have blue hydrangeas (though I am partial to pink ones). You can turn a pink hydrangea blue by adding a mixture of a tablespoon of aluminum sulfate (available at any nursery) to a gallon of water and put this in the soil at the base of the plant. It also helps to have a soil pH of 5.0 to 5.5.
Another easy to grow summer perennial is the daylily. They come in a great collection of colors with both single and double-bloom varieties. They spread vigorously in your garden and year to year you can dig up the bulbs, divide them and spread them elsewhere in your garden. The only care they need is to deadhead them to remove the spent blooms and trim the foliage when it flops in the fall.
One of my favorite perennials is the coneflower or echinacea. This also comes in a variety of colors and it is a particular favorite of butterflies. And it will come back year to year and it even spreads with new plants. It will get one to two feet all and it really stands out in a garden bed.
Iris are fairly easy to grow. They sprout from a bulb which grows fairly close to the surface. In fact, sometimes they grow out of the soil and they have to be replanted shallow. They too come is a variety of colors, tending toward blue, purple and yellow. There are more than 100 species of irises.
Gladioli also grow from bulbs and they are simply beautiful with their color palette. They are particularly good for cut flower arrangements. Glads grow 2 to 3 feet tall before they explode in a wonderful display of colors. With glads it is normally best to dig up the corms about the time of the first frost and store them in peat moss in a cool (50 degree) part of your house. If left in the ground they might rot in a cold winter. Because we had such a mild winter last year a few of mine that I forgot about are thriving in bloom right now.
I haven't yet gotten to my three favorite perennials. Perhaps in the future I will talk about dahlias, cannas and calla lilies. More on them and others perhaps next week.
The above are a few of my favorite perennials. What are YOUR FAVORITES? Add a comment below or email me at firstname.lastname@example.org and let me know. Till next week.
Be sure to bring your gardening questions and a soil sample to us at our Gardening Information/Soil Testing kiosk at Paradise Valley Park (Paradise and Prospect Avenues in Middletown). We are there every Sunday (rain or shine) from noon till 2 pm.