Sanhedrin Nursery – Garden Blog

• Rhododendrons are in full bloom now. Choose plants now for spectacular blooms in your shade garden.

• 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.

• 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.

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

• Colorful Gerberas with their large, daisy flowers are a standout in containers. Water them infrequently and give them plenty of sun for flowers all summer.

Get Growing with Season Extenders

Most home gardeners are anxious for that first ripe tomato or early muskmelon. Gardeners who sell produce at local farmers’ markets also strive for the earliest crop possible because early produce often brings better prices at the market.

To get the most out of a garden, you can extend the growing season by sheltering plants from cold weather both in early spring and during the fall. Very ambitious gardeners harvest greens and other cool-weather crops all winter by providing the right conditions. There are many ways to lengthen the growing season and hasten growth and production in your vegetable plants. Your choice depends on the amount of time and money you want to invest.

Cold frames are simple structures providing a favorable environment for growing cool-weather crops in the very early spring and for hardening-off seedlings that were started indoors or in a greenhouse. This hardening-off period is important as seedlings can suffer serious setbacks if they are moved directly from the warmth and protection of the house to the garden. The cold frame provides a transition period for gradual adjustment to the outdoor weather.

Hot caps are cones of translucent paper or plastic that are placed over the tops of plants in the spring. These act as miniature greenhouses for small plants. Gallon milk jugs with the bottoms cut off and the caps removed work well as hot caps. Originally a cloche, a bell-shaped glass jar, was set over delicate plants to protect them from drying winds and cold air.

The newest version of a hot cap is the “Season Starter”, previously called “Wall-O-Water”. They are larger than hot caps and provide much longer protection for the plant. They consist of a series of tubes that are filled with water, which collect heat during the day and release it at night. They can be set up in the garden 6 to 8 weeks before the typical planting date. Fill them with water a week before the transplants are planted in them to warm the soil in that area. It will protect plants down to 20º F, and last for 3-5 seasons.

Floating row covers are lightweight fabrics that are laid over a row of plants to protect them. They are composed of spun-bonded polyester and come in various widths — 6 feet or wider. Row covers keep plants 5-10 degrees warmer than the surrounding air and provide frost protection to a low of 28 degrees. They allow light and water through to the crop and protect tender plants from wind and rain damage as well as insects. They are intended to “float” over the row with edges held in place with soil.

With this unseasonable May weather, it is a good idea to provide some warmth and protection for your vegetable starts. You will be rewarded with juicy, homegrown vegetables once summer weather arrives.

• Plant an herb garden in a container near the kitchen door for convenient fresh spices like basil, oregano, parsley and sage.

• Potatoes can still be planted this month. Plant red, white, yellow and russet for a variety of uses and flavors.

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

• Tomatoes are the most popular summer vegetable. Choose from the many varieties available now so you can enjoy delicious home-grown flavor.

• Mulch blueberry plants with aged sawdust and feed with cottonseed meal or an acid fertilizer.

Glorious Rhododendrons

There are few sights more beautiful in the plant world than a mature rhododendron covered with large, rounded trusses of bright, colorful flowers. These large shrubs can be used to enclose the shade garden and give you flowers to enjoy each spring.

The rhododendrons that we are most familiar with represent a small portion of the rhododendron family. Varying from ground cover shrublets with needlelike leaves to large-leafed tree types, the more than 900 species comprise a very large family. While most of the species are native to eastern Asia — from Siberia to New Guinea — they also grow naturally in Appalachia as well as in our coastal forests.

Rhododendrons have been hybridized for more than a century. By crossing species, we now have rhododendron hybrids that are tough, adaptable and easy to propagate. Attractive foliage, vigorous, trouble-free growth and large, colorful flower clusters have been some of the goals of hybridization.

To successfully grow rhododendrons, you need the right soil and exposure. These plants are shallow rooted and need moisture and oxygen in the root area to flourish. They do best in soil with plenty of organic matter and good drainage. In poorly drained sites, build a raised bed or build a mound so that the rootball is above the existing ground level. Plants should be planted no deeper than they were in the container. It is better to err on the side of too shallow than planting them too deep.

Acid soil is also necessary for good growth. Check the pH of the soil and add soil sulfur, if necessary, to bring it down to 5.5 to 6.0. You can fertilize once or twice a year in the spring with an acid fertilizer, but established, healthy plants need little or no fertilizer.

Although rhododendrons like the shade, they need some sunlight in order to bloom. Three or four hours of morning sun are ideal, but they can also have late afternoon sun or filtered sun all day through overhead branches or trellises. Insufficient sunlight is often the cause of poor blooming and leggy plants.

Rhododendrons need water through the summer months. Keep cultivation around them to a minimum, due to their shallow roots, and use mulches to control weeds, conserve moisture, and provide more uniform soil temperatures. Mulches can be made of sawdust, decorative bark, straw, or other organic materials.

Rhododendrons come in a rainbow of colors from pure white, through shades of pink and lavender to bright reds and purples. There are a few yellow or cream-colored rhododendrons also. They all are welcome sights in the garden each spring.

• Mother’s Day is the perfect time to give a gift of a living plant. Rhododendrons, lilacs, hanging fuchsias and ivy geraniums are sure to please her.

• It’s time to put out oriole feeders. You can also attract them with fresh orange halves.

• Flower seeds can be sown directly in the garden now. Cosmos, marigolds and zinnias will give you beautiful flowers all summer.

• Feed roses to encourage a beautiful display of color later this month. Treat plants to prevent insect and disease problems.

• Plant the vegetable garden this month, but remember that late frosts can still nip tender young plants.

Butterfly Garden

One of the joys of summer is watching the butterflies visit your garden. You’ll enjoy them even more by planting flowers that they like to visit.

The main food of adult butterflies is flower nectar. Some flowers contain more nectar, and are more appealing to butterflies than others.

Nectar plants should be of various heights, because smaller species of butterflies often stay low, while larger species often prefer to stay high when feeding. When planning a garden, plant several of each flower species to attract butterflies and nectar bearing flowers that bloom in sequence over a long season.

Nectar plants can be perennials, annuals or shrubs. Lilacs and the native Ceanothus are among the earliest plants which will attract butterflies. Butterfly bush (Buddleia davidii) has graceful plumes of purple flowers that bloom in the summer. Bluebeard (Caryopteris) blooms from late summer into the fall with its lovely sky-blue flowers.

There are many perennials that provide nectar. Spring-bloomers include purple rock cress (Aubrieta), chives and forget-me-nots. There are numerous summer-blooming perennials that attract butterflies. The daisy family provides a lot of them with Gloriosa daisies (Rudbeckia), coreopsis, Shasta daisies, blanket flower (Gaillardia) and purple coneflower (Echinacea). Sunflowers, with their many color choices, will give you some tall plants for the back of the border.

Other good choices are bee balm (Monarda), butterfly weed (Asclepias), lavender, gay-feather (Liatris), pincushion flowers (Scabiosa) and summer phlox. Yarrows (Achillea), catnip, verbena and red valerian (Centranthus) will also attract butterflies.

You can fill in the flower bed with annuals like marigolds, ageratum, cosmos, heliotrope, verbena and zinnias. These can give you varying heights and flowers over a long season.

For the end of the season, asters like Michaelmas daisy and showy sedum (Sedum spectabilis) will provide nectar for the last generation of butterflies.

There are many more plants which are attractive to butterflies and part of the fun of ‘butterfly gardening’ is experimenting and seeing who comes to dinner.

Although nectar sources alone may attract butterflies, only the planting of caterpillar host plants defines true butterfly gardening. They provide a site for the butterfly to lay eggs and also a food source for the emerging caterpillars. In most cases, they won’t be interested in your shrubs or flowers. They would rather eat plants like clover, plantain, parsley and dill or the leaves of birch and willow trees. Be prepared for heavy munching on your host plants!

Use insecticides sparingly because most garden insecticides can kill the caterpillar stages of the insects. Adult butterflies also can be killed by resting on insecticide-treated surfaces.

You will also want some still water for butterflies to drink.  A birdbath can often give a butterfly a necessary drink.  Swallowtails will often congregate around wet gravel.

The butterfly garden is wonderful fun for kids and adults alike.