How do you deal with overgrown carpets of goutweed that defy pruning? What's to be done with crowded lilacs? And what about sprawling mats of iris that show promise but barely bud? Should you remove these plants and shrubs, or coax them into bloom by ruthless trimming, reducing, and dividing?
The best approach is not to be hasty. If you dig up the garden prematurely, you may unwittingly destroy bulbs or a desirable heirloom plant that was less noticeable than its more vigorous neighbors. Be especially prudent when removing trees or shrubs, since they take years, even decades, to grow to maturity.
During the first season you spend with your inherited garden, observe what's growing from early spring through autumn, and record what you see. Draw a rough diagram of the garden, recording location, bloom time, color, and names (if possible) of all the plants. In the fall, spread a thick, nutrient-rich organic mulch, such as rotted manure or compost, over the entire garden. This will help soften the soil and make weeding and dividing much easier come spring.
If you're having difficulty deciding what to save and what to discard, take care not to throw out common plants, because they may prove useful somewhere else on your property. Robust survivors, like the common orange daylily (Hemerocallis fulva) and hostas, for instance, have potential as ground covers where little else will grow. Cream-variegated goutweed (Aegopodium podagraria 'Variegatum') can light up a dark corner or make an eye-catching hedge if kept mown on both sides. Just as you lovingly restore and preserve the history of your old house, it's wise to take the same level of care to the land on which it sits. A thoughtful plan will help you to create a satisfying new garden from the remnants of the old.