Garden Detective: Readers ask about purple plum tree, Liriope and star magnolia

A young purple plum tree grows in reader John Vogt's South Huntington garden. Credit: John Vogt
DEAR JESSICA: This small plant or bush was installed by the previous owner of my home some seven years ago, and I don’t know what it is. Its delicate flowers are very pretty but it’s a bit leggy, so I’m thinking of transplanting it. — John Vogt, South Huntington
DEAR JOHN: That’s a purple plum tree (Prunus cerasifera), a fast-growing but short-lived specimen with striking purple leaves and beautiful pale pink flowers that are among the earliest spring bloomers.
To ensure the foliage remains purple, pick a sunny spot when relocating it, as leaves tend to turn green in the shade. Over an average life span of about 20 years, the trees grow 15 to 20 feet tall but are susceptible to a host of diseases and insects, including Japanese beetle attacks.
DEAR JESSICA: This plant has invaded my flower beds. It started with just a few, but over the past two years it has taken over, and it doesn’t die off over the winter. I tried to pull some new shoots out, and they seem to be attached by underground roots. I had planted perennials that are all being choked out. What is it and how do I get rid of it? — Susan Leon, Commack

Liriope fills in a garden border outside reader Susan Leon's home. Credit: Susan Leon
DEAR SUSAN: That’s a beautiful, abundant bed of Liriope, which are covering the bare soil (and outcompeting weeds). You’ve likely noticed that they send up spikes of pretty purple (or white) flowers in summer that give way to berries. One of its desirable attributes is that it remains green for most or all of the year.
Commonly called “lilyturf” (and sometimes “monkey grass”), Liriope is an exotic slow-spreading plant that’s not related to grass at all, but rather is a member of the asparagus family. It’s often used to prevent erosion on hills, as a ground cover or weed-suppressing edging plant.
Those underground roots you’ve noticed connecting plants are called stolons. They travel horizontally and send up new plants from their ends.
The best way to eliminate Liriope is to dig out clumps, ensuring that you turn over the soil to reveal the stolons and remove them, as well. You’re sure to leave some behind, so there will likely be a need for maintenance removal for several years.
DEAR JESSICA: I love this tree that’s growing in front of my gym in St. James. I’ve asked everyone, even the maintenance guy at the gym and my landscapers, if they can identify it, and no one knows! The coolest feature is the giant, fuzzy, pussy-willow-type buds that are present for most of the winter into early spring. Can you tell me what it is, and when the ideal planting time would be? I’d like to get one as soon as possible. — Melissa Friend, St. James

Magnolia stellata tree in bloom in an early spring. Credit: Getty Images/iStockphoto/Irina Drazowa-Fischer
DEAR MELISSA: That’s a star magnolia tree. The medium- to fast-growing Japanese native can be expected to reach 15 to 20 feet tall with a spread of 10 to 15 feet, growing as much as two feet per year, but can be trained into shrub form.
Fragrant, white, 4-inch double blossoms cover bare branches in spring, before the emergence of oblong glossy green leaves.
Plant it in full sun to part shade, in rich, well-draining soil, then apply 3 to 4 inches of mulch around the tree, taking care to keep mulch a few inches from the trunk to avoid rot. Water regularly for the entire first year until the tree becomes established, taking care not to allow the soil to become soggy (some supplemental watering may be necessary during hot, dry spells during the life of the tree). And apply a fertilizer for acid-loving plants, according to package directions, annually in spring.
DEAR READERS: Several readers have written to ask why I recommended that bird feeders be removed and stored for the summer. Although it may seem helpful to feed our feathered friends year-round, it isn’t necessary and can be counterproductive.
It’s important to supplement birds’ diets during winter, when seeds, their natural food source, are scarce. It’s also helpful because that’s when many birds are migrating south, so their energy needs increase in preparation for their journeys. Providing food during this time helps our native birds as well as those passing through.
But food is typically plentiful for birds during spring and summer. Spring also is when birds are nesting and feeding insects and worms to newly hatched chicks. Once mobile, those babies will need to learn the lessons of foraging for themselves.
There's still time to plant your own pandemic "victory garden": Find tips and resources here.