Just Ask: Go slow on love to keep shrub in line

Q: I fell in love with a Rose of Sharon shrub that I saw in bloom at the nursery. It is the variety 'Blue Bird' and the tag says it will grow 15 feet tall and 6 to 8 feet wide. Now I have to find room for this new plant, but my garden is already quite full. My question is can I keep it smaller with pruning and if not, how fast will it grow?

-- M., e-mail

MB: Nothing like a late-blooming Rose of Sharon (Hardy Hibiscus syriacus) to bring the bluebird of happiness to an autumn garden. But before you place and plant this exotic-looking shrub, you need to hear the garden gossip. This hardy hibiscus sits around naked for more than half the year. The foliage falls early in November and then the shrub doesn't turn over a new leaf until May. The good news is you can control the size of your Rose of Sharon shrub with yearly pruning each spring. In my garden, a Rose of Sharon hibiscus grew slowly and it took 20 years for an initial 3-foot shrub to reach 12 feet tall -- but then I'm not the type of gardener who will fertilize much or offer extra water. If you shower your new love with attention, food and water, it will grow much faster.

Q: Isn't it true that slugs are imports from Europe? My neighbor feels it is cruel to kill slugs because they were here before we were, but I seem to remember hearing that they are an invasive species and need to be controlled! I am quite sure that the slugs from her yard come over to my garden.

-- M.G., Olympia

MB: You're both right. Most garden slugs are European imports and they do need to be controlled -- some years up to two-thirds of the strawberry crop in our state is devoured by slugs. But we also have native slugs. These are the large, pale-green or yellow banana slugs that move slower and seem to prefer woodland debris over crops and garden plants. A third slug is the great gray garden slug with leopard- or tigerlike black markings, and this fast (for a slug, anyway) and aggressive slug goes around attacking both our native slugs and the smaller milky slugs. Slugs do provide food for snakes and other creatures, so we need them in the food chain. I suggest a compromise. Designate a slug-free zone where you can group your hostas, lettuce, marigolds and other tender plants and then do slime patrol at night. Use Worry Free slug bait or something similar and keep a clean garden to control the population. Outside this area, let the slugs fight it out where you grow slug-resistant and native plants. Most plants with thick, shiny, furry or needlelike leaves survive these slime balls. To control any illegal immigrants from your neighbor's garden, consider a strip of copper along the property line. Slugs don't like to cross copper, as their slime sets off a small electrical shock. I also have seen a battery-powered slug fence (really!) that will keep out slugs.