Tip of the Week — 6/22/09

Posted in Gardening Tips on June 22 2009, by Sonia Uyterhoeven

We All Need Friends: Companion Planting for Roses

Sonia Uyterhoeven is Gardener for Public Education. Join her each weekend for home gardening demonstrations on a variety of topics in the Home Gardening Center and for part of June in the Rose Garden.

We all need friends—roses are no exception. As the season progresses, roses start to lose their bottom foliage and show their bare legs. Repeat bloomers also have moments between flowering cycles when they are devoid of color. Companion plants are easy solutions to dress up your roses and make them look their best.

When choosing a good companion, it is important to find a plant that does not compete with the rose for water and fertilizer and does not restrict air flow—sufficient air circulation is needed to prevent black spot and other fungal problems.  

Good companions for roses include the classics such as lavender (Lavandula), catmint (Nepeta), and salvia (Salvia) whose wispy spires hide blemishes on the rose’s foliage. Many easygoing annuals such as summer snapdragon (Angelonia), lantana (Lantana), and verbena (Verbena) make excellent partners as well. Plant the companions at least a foot away from the rose so as not to disturb the rose’s roots.

One of my favorite ornamental sages or salvias in the garden is Salvia nemorosa ‘Caradonna’. It keeps a nice, upright, well-maintained look throughout the season and flowers from June until September if deadheaded.

If you haven’t tried summer snapdragons in your seasonal repertoire, then add them to your list. Angelonia or summer snapdragon has the advantage over the traditional snapdragons (Antirrhinum) as they flower dependably throughout the summer with just a little deadheading. Angelonia ‘AngelMist™ Lavender Bicolor’ is a superb bicolor cultivar whose pale colors blend beautifully with neighboring plants.

Sometimes good companions are plants that enhance growth and protect each other from harm. Members of the onion family, including chives and ornamental onions (Allium) are rumored to increase the rose’s perfume, ward off aphids, and prevent black spot. Scented geraniums (Pelargonium), rue (Ruta), thyme (Thymus), and parsley (Petroselinum) purportedly repel Japanese beetles. There are many interesting companions to suit any size or color of rose that you may have.