Sanhedrin Nursery – Garden Blog

• Last chance for asparagus roots this year. Prepare a fertile bed for these long-lived vegetables.

• Potatoes like to grow in the cool weather of spring. Plant them as soon as possible.

• Tree peonies are long-lived shrubs that are available now as root divisions. Their large, fragrant flowers bloom for two months each spring.

• Wildflower seeds can be broadcasted now on hillsides for colorful blooms and erosion control.

• Lettuce, cabbages, broccoli, onions and other cool-season vegetables can be set out with no frost protection. They will give you a delicious early harvest.

The Beauty of Begonias

If you have shady garden areas or are looking for a brilliant accent for your patio or balcony this summer, you can start some tuberous begonias indoors in March or April. Tuberous begonias provide a spectacular display from July through October and come in white, pink, red, yellow, orange, and apricot.

There are upright begonias and hanging begonias and they grow from tubers which look like small brown lumps with a depression on one side. Choose only firm tubers and look for those with tiny sprouts showing on their upper, concave surfaces.

Start with small, clean pots 2 to 3 inches deep. Fill them with a mixture of equal parts of potting soil, peat moss and sand or perlite. Place each tuber hollow side up with the top just even with the soil level. They rot easily if planted too deep. Water the tubers once really well, to wake them up, and place them in a warm, bright spot.

Cover the freshly-planted tubers with plastic wrap to promote growth, but remove the covering as soon as growth appears. Don’t water again until you see some growth or the soil is quite dry. Some begonias will sprout right away others will take weeks, but you should see growth shoots within a month.

Once the shoots are showing, water them regularly, never allowing the soil to dry out. Give the new plants bright light, but shade them from direct sun. Feed them with half strength fertilizer when their leaves and stems are about 3 inches tall, and every two weeks after that. When the shoots are 6 inches tall, the begonias are ready to be transplanted to the garden or outdoor containers. Don’t put them outdoors, though, until all danger of frost has passed, and remember to harden them off properly first.

Tuberous begonias thrive in partial to full shade and need well-drained soil. They need to be kept away from hot sun and drying winds. Water them generously, especially during hot weather. Keep their soil moist but not soggy; the tubers will rot if they get too much water. Keep an eye out for mildew and first sign of a white patch on any of your begonias’ leaves, apply a fungicide right away.

If you’re growing hanging types, pinch out the primary growing tip when the plant is about 2 inches tall to make sure they have lots of branches to cascade down from their pots. Plant 3 tubers in a hanging basket.

Deadhead begonias regularly, removing wilted leaves and flowers to encourage them to produce more blooms. The large-flowered, upright types of begonias should be staked.

Once the show is over in the fall, you’ll be able to dig and store your tubers until spring rolls round again. Properly stored, tuberous begonias will give you years of vibrant, eye-popping blooms to brighten up your shady garden areas. So get your tubers started now for a show-stopping summer!

• Thin fruit trees now while fruits are still small. Thin apples to 6 inches apart and peaches to 4 inches apart. On Asian pears leave 1 fruit per spur.

• Wisterias are large, vigorous vines that are blooming right now with their long clusters of purple, pink or white fragrant flowers. Give them a strong arbor to climb on.

• When you plant your tomatoes, put a handful of bone meal in the bottom of the hole to help prevent blossom end rot on the fruit later on.

• Spray roses every two weeks to keep them healthy and prevent leaf diseases. Neem oil is a safe alternative to chemicals.

• Ivy geraniums make wonderful hanging baskets for partially shaded spots where they will bloom all summer.

A Beauty in the Shade Garden

It is sometimes difficult to design a shade garden with lots of color. Most plants do not flower well in too much shade. But Impatiens are easy-to-grow and flower in shady areas all summer long.

Impatiens came originally from Zanzibar, an island off the coast of Tanzania. In the 1950’s, hybridizers began working with Impatiens to improve plant qualities. New varieties were introduced in the 1960’s as this new bedding plant began to catch on. Now Impatiens are the most popular bedding plant in the country.

Common names for Impatiens, like ‘Busy Lizzy’ and ‘Touch-me-not’, hint that this plant is indeed “impatient.” When the seed pods are ripe and full, the slightest touch will cause them to burst open and scatter their seeds in the wind.

Hybrid Impatiens come in a full range of colors. Flowers are up to two inches across completely covering the 12 to 18 inch plants. Colors include red, white, orange, coral, pink, rose, lilac, lavender-blue and burgundy as well as picotee bicolors, which are striped or splashed with white. There are also double-flowered varieties known as “rosebud” Impatiens.

New Guinea Impatiens are quite extraordinary with 2-3 inch flowers and very large leaves that are often variegated with cream or red. Plants grow 1 to 2 feet tall by summer’s end in rich, moist soil. They grow well as container plants and will take more sun than other Impatiens.

Impatiens are easy to grow in partial shade, in rich, moist soil. In too much sunlight, they will have small leaves and few blooms. They also do not perform well in deep shade, where there is no hint of sunlight for any part of the day, but thrive in filtered shade along with begonias, ferns, foxglove, hydrangeas and fuchsias. The plants will tolerate morning sun, but by noon they need to be in the shade or the summer sun will cook them.

Impatiens do best when given a well-prepared, relatively fertile soil that can be kept on the moist side during the summer. Consistent moisture is the trick to premium impatiens flowers. Never let the soil dry out completely. Those grown in the soil under trees will need extra water and fertilizer due to competing with the tree roots.

Moss baskets look wonderful planted with Impatiens. As they grow, they completely surround the container with flowers. They are excellent in window boxes and make wonderful drifts of color bordering lawns and pathways.

Covering themselves with flowers all summer, Impatiens are perhaps the most useful summer annual for shady gardens.

• Roses need water and fertilizer to keep blooming through the summer. Watch for pests and diseases and treat as soon as you see trouble.

• Birdbaths will attract our feathered friends to your backyard so you can enjoy them close-up. Place them a few feet from a bushy shrub to give the birds protection.

• Zinnias love the heat and will add a rainbow of color to your garden and the deer don’t like them.

• Fragrant star jasmine is in full bloom right now. Plant one in a semi-shaded spot where you can enjoy its lovely perfume.

• Prune camellias and azaleas to shape them now. If you wait much longer, you will be cutting off next year’s flowers.

Summer Beauty in the Shade

The big, round, pink flower clusters of the well-known hydrangea have decorated summer gardens in California for decades. These long-blooming bushes are ideal for shady areas of the garden, as they bloom for most of the summer.

From their home along the rivers of China and Japan, hydrangeas were brought to Europe by plant collectors in the 1800s and now are popular in many parts of the world.

The name Hydrangea gives us a clue to the main needs of this plant. It comes from the Greek word Hydro, meaning water, indicating its need for plenty of water in the summertime. Hydrangeas prefer moist, humus-rich soil with good drainage. So when planting, add peat moss and compost to the soil.

Hydrangeas cannot tolerate hot sun. It will burn their leaves quickly. Plant them where they receive only early morning sun. The north side of a building is usually a good location. They need regular watering and should not be allowed to dry out. Plants wilt if they get too dry but will recover soon with a thorough watering.

Pink hydrangeas can be made to turn blue by making the soil more acid. This is done by working aluminum sulfate into the soil around the plants in March. Flowers may turn blue naturally here where the soils are acidic under conifers. It you want to keep the flowers pink, apply lime around the plants in the springtime.

Hydrangeas are deciduous shrubs which lose their leaves in the winter. They can be pruned when dormant by removing spent flowers down to a healthy pair of buds. This should be done in spring when they first start to show new growth.  

There are many kinds of hydrangeas besides the common one. The lace-cap hydrangea has flower heads that are made up of a cluster of small flowers surrounded by a ring of large ones. They may be white, pink or blue and add a dramatic touch to the shade garden. Some have variegated leaves which add color in shady areas.

There are several new cultivars including ‘Endless Summer’, ‘All Summer Beauty’, and ‘Glowing Embers’. They add some variety to the sizes and colors of standard hydrangeas.

Few vines have as much to offer as the Climbing Hydrangea. They provide interest year ’round: cinnamon-colored, bark and dried blooms in winter; fragrant, ivory colored flowers like those of lace-cap hydrangea in early summer; lush, shiny green foliage through the growing season that turn golden yellow in the fall. This vine is the clinging type, so a trellis is not necessary.

Hydrangeas grow quite large on the coast, but usually stay under five feet here. They give us some of our best summer color. Good companion plants include hostas, astilbe, columbines and bleeding hearts. Planted with pink, lavender or white impatiens around their base, they will bring life and color to your yard all summer.