Archive | May, 2013

Aster

20 May

450px-Aster_alpinus_002Aster, deciduous perennial, 12 to 24 inches in height, large clusters of daisy-like flowers in many colors including blue, purple and white, dark green hairy foliage, full sun to part shade, great cut flower, divide yearly, Aster chilensis is native.

There are more than 600 species of true asters, ranging from 6-in.-high alpine kinds forming compact mounds to open-branching 6-ft.-tall plants. Flowers come in white or shades of blue, red, pink, lavender, or purple, mostly with yellow centers. Bloom time is generally in late summer to early fall.

Taller asters are invaluable for abundant color in large borders or among shrubs. Large sprays effective inarrangements. Compact dwarf or cushion types make tidy edgings, mounds of color in rock gardens, good container plants.

aster-prenanthoides-2009-10-24-zoo-01

True asters are adapted to most soils, but growth is most luxuriant in fertile soil. They have few problems except for mildew on leaves in late fall. Strong-growing hybrids have invasive roots; they can regrow from small fragments left in soil and spread to become nuisances. Divide yearly in late fall or early spring. Replant vigorous young divisions from outside of clump; discard old center. Divide smaller, tufted, less vigorously growing kinds every 2 years.

officialAster novi-belgii 

Native to eastern North America. To 4 ft. tall, 3 ft. wide, with full clusters of bright blue-violet flowers. Similar toA. novae-angliae but with smooth leaves. Hundreds of selections are available, varying in height from less than a foot to over 4 ft.; flower colors include white, cream, blue, lavender, purple, rose, and pink.

Magnolia

18 May

Magnolia-300x225Magnolia, small to medium sized deciduous tree, 12 to over 20 ft. in height, spring blossoms range in color from white to nearly black, attractive structure and foliage.

Magnolias are magnificent flowering plants featuring blossoms in white, pink, red, purple, or a more recent development, rich yellow. specialists.

Magnolias include both evergreen and deciduous types. Most have large, striking blossoms composed of petal-like segments, but a few are grown for use as foliage plants.

For any magnolia, choose planting site carefully—virtually all these trees are hard to move once established. Magnolias never look their best when crowded. Pick a location where the shallow, fleshy roots won’t be damaged by digging or by soil compaction from constant foot traffic. All magnolias may be used as lawn trees; try to provide a good-size grass-free area around the trunk, and don’t plant under the tree.

Magnolias appreciate fairly rich, well-drained, neutral to slightly acid soil amended with plenty of organic matter at planting time. They will grow in somewhat alkaline soil but may develop chlorosis.

At least in the early years, keep a cooling mulch over the root area.

Irrigate deeply and thoroughly, but don’t waterlog the soil or the tree will drown. Only M. virginiana can take constantly wet soil.

Feed trees if new growth is scanty or weak, or if you see significant dieback despite adequate watering and drainage; use a controlled-release product. Treat chlorosis (lack of iron—common in alkaline soils—that shows up as yellowing between leaf veins) with iron chelates.

Leaf damage can result from excess mineral salts in the soil or salts in irrigation water. The latter is a problem in Southern California and, typically, the factor limiting success of magnolias in desert regions. Frequent heavy waterings will help leach out salts and carry them to lower soil levels—as long as drainage is good.