Maggie’s Tips for Growing Roses

Maggie Easton

Roses are often called the “Queen of Flowers”. They are probably the best-loved garden flower, which is understandable since there is a rose for every taste. They come in a range of sizes from 6 in. miniatures to climbers that top 40 ft. They can be climbers or spreaders, erect growing or lax, and anything in between. Their flowers can be as small as ½ in. across to better than 6 in. and they come in a wide range of colours, lacking only shades of blue. The blossoms can be single with just five petals, or so double it is difficult to count the petals. Add an enchanting fragrance for many of them and they are truly irresistible.

If you are new to growing roses or don’t want to worry about covering tender roses in the fall, there are a lot of choices. Any of the Explorer series or the Parkland series roses are winter hardy here. David Austin roses are also good survivors as long as they have some snow cover. There will be die-back, but the plant will recover quickly once it is pruned. There are also a lot of new roses on the market that are winter hardy here. I suggest talking to the staff at a local greenhouse to find a rose that will give you pleasure for many years with no more care than any other shrub or perennial in the garden.

When shopping for a rose plant, consider where it will be planted so that you buy one of an appropriate size. Please yourself as far as colour and flower type go. You can buy roses by mail-order (shipped bareroot in spring) or potted roses at a garden centre. Avoid buying roses in plastic bags at a big box store unless you are growing them as a annual. Those poor things have had their roots pruned to almost nothing and are unlikely to survive the winter. It is also quite possible that they have been grafted onto rootstock that is not hardy here. When selecting roses, look for plants that have healthy new growth and check that there is no sign of blackspot, powdery mildew or other disease. Also check that the neck between the graft and the roots is not too long. If it is, it will be difficult to plant the rose deep enough.

Roses need at least six hours of sun to bloom well and like rich, well-drained, moisture retentive soil. When planting your newly purchased rose, dig a hole big enough to allow the roots to spread, if it is bareroot. For a potted rose, make sure the hole is wider and deeper than the pot. Amend the soil with a good quality compost, especially if your soil is either very sandy or very heavy. Plant the rose so that the graft union is at least 4 in. below the soil level after the hole is filled. Press the soil around the roots by stepping down on it with your foot. This eliminates any air pockets, and ensures that the roots make good contact with the soil. Add some MYKE© if desired, and some starter fertilizer. Water well.

During the growing season, keep the rose well-watered and fertilize with a 20-20-20 granular fertilizer every two weeks until early August. Feeding roses after that date will encourage new growth which will not harden off before winter. Deadhead as needed to encourage more blooms. For hardy roses, you might want to leave the spent flowers on the bush to get a colourful crop of rosehips in the fall. These will add colour to the winter garden for most of the winter. If your rose is not a hardy rose, mulch with about 12 in. of leaves, straw, or peat moss before the ground freezes, usually in late October. I have done it in the snow, but it is much more pleasant to do it before the snow flies. Don’t prune the roses at this time.

In spring, uncover the tender roses in mid to late April depending on weather conditions. If the rose is showing new growth, it is safe to uncover earlier. Wait till the buds are well along before pruning. Pruning too early can lead to more die-back. Once the buds are well established, prune the rose bush. First remove all dead or diseased wood. Then remove crossing branches. Finally prune for shape. Always cut to an outward facing bud to encourage open growth, with good light into the centre of the bush. If you have a once-blooming rose, only remove dead and diseased wood in spring. These roses bloom on old wood and pruning out healthy wood also prunes out flowers. With hardy roses, prune out about 1/3 of the oldest canes once the bush is 3 or 4 years old. These old canes are less productive and cutting them out at ground level will stimulate new canes which give more flowers.

After pruning your roses, get them off to a good start by giving them some alfalfa meal or alfalfa pellets. Give each plant about ½ cup of the alfalfa meal or 1 cup of alfalfa pellets. Alfalfa contains a growth hormone that leads to healthier, faster growth and more bloom. A handful of Epsom salts is also beneficial to roses. Cover the alfalfa meal with mulch, because it turns a really icky colour when it is wet. I use two inches of compost as mulch.

Happy growing! Enjoy your roses!

[Maggie has been growing roses in her Millwoods garden for many years and has won EHS Garden Competition awards for her garden and her roses. – Ed.]

(Originally published in Gardener's Gate, August 2011.)