Sanhedrin Nursery – Garden Blog

• Trim foliage on grape vines to allow more sun to reach the fruit and ripen the grapes.

• If your bearded iris blooms were sparse this year or the plants are more than four years old, now is the time to divide and replant them. Mix some bone meal into the soil, and plant the rhizomes just beneath the soil surface.

• Lilac bushes will bloom better next spring if you cut back on the watering now.

• Keep apples picked up from under the trees to help control the spread of coddling moths which make wormy apples.

• Cover newly planted vegetable starts to protect them from birds. Spray cabbage and broccoli plants with BT to control cabbage worms which make holes in the leaves.

Low-maintenance Perennials

Perennials give us some of the best flowers in the garden. These hardy plants come back year after year getting bigger and better each time. Most perennials take a lot of dead-heading to keep them looking nice throughout their blooming time, but there are a few that are easier to care for. Cut them down when they are done flowering and that’s all the maintenance they need.

Sedum Autumn Joy is a well-known favorite that attracts butterflies. The leaves grow close to the ground, then once a year it sends up shoots topped with soft pink flowers, similar to yarrow. As the days get shorter, the flowers turn a rich rusty red.

Moonbeam Coreopsis produces star-like blossoms of pale yellow with finely textured foliage that is good-looking all season. It blooms from July through October and spreads 18-24” wide.

Black-eyed Susan, Rudbeckia fulgida ‘Goldsturm’, grows into a large clump with 3’ tall golden, black-centered, daisy flowers bloom from August to October.  Seed heads are attractive to birds in the fall and winter.

Stella D’oro Daylily has bright, golden-yellow flowers that bloom throughout the summer above fresh green leaves. It is compact, growing only 16 inches tall, and is good for containers and flower borders.

Purple Dome New England Aster is a compact aster with dark green foliage and profuse bloom of dark purple daisy flowers which can entirely cover the plant in September and October. 

Santa Barbara Daisy, Erigeron karvinskianus, is a low-growing perennial that is covered with little white daisy flowers all summer long. It is tolerate drought once established, and can be used as a border plant or to hang over a wall.

Peonies are easy to grow and give you magnificent flowers in May-June. They come in pink, white and red and live for many years, growing into a larger clump with more flowers each year.

For shady areas, Hostas can’t be beat. With their beautiful foliage in different combinations of blue, green, white and yellow, they will fill the shady bed with their colorful leaves. Hostas also bloom in the summer with spikes of lavender to white, lily-like flowers, which can be quite showy.

Heucheras, or Coral Bells, are one of the most diverse and colorful shade perennials.  Plant them as a groundcover, or intersperse some between other plants. Their round leaves come in many colors from bright green to purples to near black, and they send up delicate spikes of white or coral flowers in the summer.

Helleborus is an iron clad deer-proof plant that tolerates dry shade once established. It blooms very early, in late winter with cup-like, greenish-white flowers. Some varieties have pinkish flowers, but their broad leaves are good-looking all year.

Dicentra, or Bleeding Heart, is one of the easiest perennials to grow in the shade. The pretty little pink flowers in the spring resemble pink and white hearts, and when they are done, the plant turns yellow and dies back. Clean up dead foliage and forget about them until next year.

Fall is a good time to plant perennials. They will get established over the winter and bloom beautifully for you next year.

• Mums are the beauties of the fall garden. Choose plants now in a wide variety of colors.

• Cool season vegetables should be planted right away to insure good crops this fall.

• Take house plants outside and wash down dusty leaves. Let them dry in the shade before bringing them back inside.

• Rose of Sharon, with its hibiscus-like flowers, is a lovely summer bloomer in our climate. It grows 6 to 8 feet tall in full sun or part shade.

• Sow these vegetable seeds directly in the soil: carrots, chard, lettuce, mustard, peas, radish, spinach and root vegetables. Keep the surface of the soil moist until the seedlings are established.

Crape Myrtle Trees
beautiful in summer and fall

If your looking for a small tree to provide year-round beauty, consider a crape myrtle for your landscape. The tree gets it’s name from the appearance of the flower petals that are crinkled, resembling crepe paper. They can be planted together to make a large hedge or screen, or in a grove or a single tree can act as a specimen to create a distinctive focal point.

The trees leaf out rather late in the spring. Then about midsummer, large 6 inch flower clusters form on the ends of the branches, and bloom through the summer and fall. The flowers are truly outstanding, and come in vibrant pink, purple, watermelon red, lavender and white.

In the fall after the leaves turn yellow, orange and red and then drop, the attractive trunk and branches are revealed. The bark of the crape myrtle is mottled and smooth. With age, the grey bark peels away to reveal a reddish-brown color underneath that is attractive all winter.

Crape myrtle is actually a shrub but tree forms, which have been pruned to create one strong central trunk, are very popular. The tree form of crape myrtle will grow to a maximum height of 15 to 20 feet tall and spread about 10 feet wide.

They flower best in full-sun locations, but will tolerate light shade or morning shade. Deep shade locations are not recommended, because the tree will not flower well and will be prone to developing powdery mildew disease.

Newly planted crape myrtles should be watered often for the first summer to aid establishment. Watering should then be gradually reduced in frequency. Crape myrtles like moist, well drained soil but are drought tolerant once established. More frequent watering will make them grow faster.

To keep crape myrtles attractive, suckers should be removed on tree forms. Pruning to remove old flower clusters will promote additional blooming, but it is not necessary to prune the tree to make it bloom. Small twiggy growth should be thinned out from underneath and within the canopy.

Never cut main branches and leave stubs. These trees should be allowed to develop their natural style without whacking off their tops, which ruins the natural graceful effect of the plant.

If you like trees with lots of color and character, check out the crape myrtle. It may be just the tree your looking for to add to your home landscape.

• Plant Beets now for fall harvest. They will have a deeper red color than beets planted for spring harvest, and tend to have higher sugar levels too.

• Fall vegetables can be planted now for a fall harvest of broccoli, Brussels sprouts, cabbage, chard and lettuce.

• Trim grapevines to allow more sun to reach the fruit and sweeten the grapes, if they are being shaded heavily by the foliage.

• Feed fuchsias, begonias, summer annuals and container plants to keep them green and blooming right up until frost.

• Divide Oriental poppies and bearded iris now. Add some bone meal in the bottom of the hole when you replant them.

Exotic Pest Plants

For many decades the nursery trade has been introducing plants gathered from around the world into our gardens. Any plant that is not native to an area is called an “exotic”. Most exotics are great additions to our gardens, and many tolerate garden conditions much better than the native shrubs.

But when an exotic plant becomes a weed, reproducing on its own in the wild, it is a pest plant. Pampas grass is a typical example. Introduced from South America, it now grows wild along the coastal areas of California. Scotch broom, which takes hold in disturbed soil such as along roadsides, is also a big problem in this county.

Why are these plants a problem? Because when they are so successful at reproducing in non-native areas, they crowd out the native plants that are critical for the survival of native birds and other wildlife.

Many of these pest plants are indeed weeds even in their native environment. Yellow star thistle, one of the most widespread of these weeds, came from Russia in the 19th century in alfalfa hay. It now covers countless acres of California’s hillsides, giving the “green and gold” a bluish cast. Others have intentionally been sold by nurseries for ornamental purposes but have turned out to be weeds.

An exotic plant’s ability to reproduce requires optimal conditions. So a particular pest plant will only be a pest in certain regions.

Many plants are particularly a problem in wet areas or around ponds. Cattails and umbrella plant can be very invasive, spreading by both roots and seeds. Yellow water iris has very aggressive roots which can fill up a small pond quickly.

If you have invasive plants on your property, try suffocating small seedlings and annual plants. Place double layers of thick UV-stabilized plastic sheeting, either clear or black, over the infestation and secure the plastic with stakes or weights. Make sure the plastic extends at least five feet past the edge of the infestation on all sides. Leave the plastic in place for at least two years. This technique will kill everything beneath the plastic—invasive and non-invasive plants alike. Once the plastic is removed, sow a cover crop such as annual rye to prevent new invasions.

Mowing or cutting plants down to the ground is also effective but only if you are committed to it. You will need to mow the area three or four times a year for up to five years. This will eventually exhaust the root system and kill the plants.

Herbicides are another option but must be used with caution.

Be careful about choosing plants for wild areas of your property so that you don’t contribute to the problem.