Where to get roses

I would like to try two of the roses that Deb Terrill mentioned at a recent program. One was a large spreading shrub rose called ‘Nevada’ and the other was a deep red floribunda called ‘Europeana.’ Where should I go to buy them? L.R., Bourbonnais

Ask your local garden centers first. If they can’t get them you will need to order them from a mail order nursery. High Country Roses in Utah carries all the varieties mentioned at Deb’s program. Visit them online or call 1.435.789.3371. Roses Unlimited also has an extensive list. Visit them at www.rosesunlimitedownroot.com or call 1.864.682.7673.

Both of these nurseries sell roses grown on their own roots. Roses that have been budded, or grafted, onto the rootstock of other roses (usually multiflora or Dr. Huey roots) are more susceptible to rose rosette disease and rose mosaic virus. Also, when growing grafted roses, gardeners must contend with long, suckering stems that grow from the rootstock, below the graft union. In severe winters, the desired rose may die altogether (especially in hybrid tea roses), leaving only the suckers from the rootstock. This sometimes makes gardeners think that their rose has ‘reverted’ or changed.

Wintering mandevilla

We have several mandevilla vines that were growing on our front porch this summer. They are sitting in the garage now; what can we do to save them for next year? We don’t really have room for them in the house. G.V., Channahon

Mandevilla vines, with their leathery green leaves and large pink, rose red or white flowers, have become very popular because they require little care and bloom well from early summer until frost. When given something to twine on, they will keep growing and blooming to become very tall. (A neighbor has two pots that he trains annually to frame his entire garage doors.) You should be able to over winter the vines in an unheated garage. Leave them just as they are in the pots and place them along the warmest inside wall. You can wrap blankets around the pots for added protection. Water them very, very sparingly (only enough to keep the roots from dying out) and do not feed them over the winter. Cut them back in the spring and begin feeding and watering more in April. You can move them in and out for sun until May 15th or so, after the danger of frost has passed. They should be repotted in fresh soil at least every other year. If your garage is unattached and freezes, give them the same treatment in a cold spare room, basement or breezeway.

Growing gardenias

I have a gardenia that was loaded with buds when I bought it but it dropped all of them within days of bringing it home. The buds were perfectly green and healthy looking. What happened? J.V., Lowell, Indiana

Unfortunately, this is a common occurrence with any number of tropical or semi-tropical plants that we bring into our homes. There are several factors involved. The first is simply that plants get accustomed to the environment in which they were growing, usually a commercial greenhouse or garden center, and are suddenly thrust into a completely different climate. Since environmental factors like light, temperature and humidity stimulate the hormones that control plant responses, even a small change can trigger a reaction.

The second problem is that most homes are dry and people tend to bring plants indoors during the months when the heat is on, making the home even drier. This can be mitigated to some degree by using humidifiers. Overly-warm conditions can stunt flowering on plants as well. Nearly all houseplants, except some carnivores and orchids from low elevation jungles, bloom best when temperatures are between 50 and 60 degrees. Standard moth orchids, gardenias, cyclamen and amaryllis all prefer cooler temps than the average homeowner prefers. Keep these plants out of direct afternoon sun and away from heat sources.

The good news is that after your plant has become accustomed to its new environment, it will probably bud out again. Wait until it has been in the house a number of weeks before feeding and then feed it with a half strength dose of fertilizer. Don’t overwater. More houseplants succumb to overwatering than any other problem. Let the soil dry out some between waterings. You need to actually stick your finger way down in the pot to check the soil moisture; you can’t tell from the surface.

Winter interest

I would like to plant some shrubs next spring that add interest to my garden in the winter. Any suggestions? F.A.H., St. Anne

Washington Hawthorne (Crataegus phaenopyrum) is one choice. A small tree that can be purchased as a single or multiple stemmed specimen, it has bright red fruits that are relished in winter by cardinals and cedar waxwings. The berries are somewhat hard and dry, making them suitable for holiday decorating, too. Ornamental grasses provide winter interest in the form of amber foliage and fluffy seed heads. One favorite is the slender maiden grass (Miscanthus sinensis ‘gracilimus’). Boxwood and false cypress are often overlooked as good candidates for the winter garden. Boxwood is indispensable for structure and false cypress (Chameacyparis species) offers many unusual shapes and textures, most of which will withstand light shade. Chokeberry (Aronia arbutifolia ‘brilliantissima’) appreciates slightly more acidic and wet soils, but has loads of bright red berries that birds won’t eat…so you can use them decoratively. Leatherleaf viburnums (Viburnum rhytidophyllum) and its cultivars such as ‘Alleghany’ and ‘Willowwood’ make very interesting winter specimens because they keep their large leathery leaves through much of the winter. A good, pink flowered azalea called ‘Karen’ stays low and the leaves turn red, then deep purple in winter.

Overwintering herbs

I want to bring my herbs in for the winter. Which ones are best to bring in and how should I treat them? D.P., Lemont

Herbs that are winter hardy may be left in the garden. These include sage, thyme, oregano and mints. If you would like to continue snipping leaves after November, try covering the plants with a glass cloche or large glass jar that is tipped slightly at the bottom to vent air.

Rosemary, basil and chives can be grown easily in the house with enough sunlight. Only a south or west window will do without supplementing light artificially. Cut basil and chives back to force new growth. Do not feed herbs; it will make them taste bland. Herbs grown in the house will be much less potent anyway because sunlight develops the flavinoids or essential oils.

Always repot any plant brought in from the garden to check for insects and other problems.

Creating privacy

I would love to have some enclosure in my backyard that would disguise a neighbor’s chain link fence and allow me a little privacy. Apart from a boring hedge or privacy fence, what could I do? I have a typical flat, square subdivision backyard. P.K., Bradley

You could create a more interesting space by changing the elevation slightly and creating a walled garden. Begin by excavating a foot or two to create a ‘floor.’ Build a low stone wall along the borders where you want privacy and use the excavated soil to build a raised bed on the backside of the wall. Add compost and other soil amendments and plant shrubs and perennials in the raised beds. This should bring the total elevation, with plants, from your side to at least 5 feet, enough to get a sense of enclosure and privacy. Another solution would be a mixed border of evergreen and deciduous shrubs along the property line. Viburnums, arborvitae and spirea would provide seasonal interest.