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Aug 172012
 

Bulbs can be categorized into groups, based on growth characteristics or intended use, making selection easier. Useful groupings include season of bloom and hardiness.


Daffodils

Daffodils are among the favorite spring bulbs

Spring Flowering Bulbs

When considering bulbs, most people think of the common spring blooming flowers, including the crocus, daffodil, and tulip. These are plants that emerge relatively early in the spring, bloom for a short period of time, then die back and wait for next spring to repeat the process. These bulbs are usually hardy under most Idaho conditions and once planted need minimal care. Spring bulbs suitable for planting in Idaho include:

Common Name
Scientific Name
Relative Bloom Time
Regional Adaptation
Anemone Anemone Blanda Mid-spring N, SW, SC
Cammassia Cammassia leichtlinii Late spring N, SW, SC, SE
Chionodoxa Chionodoxa forbesii Early spring N, SW, SC, SE, HA
Crocus Crocus spp. Very early to mid-spring N, SW, SC, SE, HA
Daffodil Narcissus spp. Early to late spring N, SW, SC, SE, HA
Fritillaria Fritillaria spp. Mid-spring N, SW, SC, SE
Grape Hyacinth Muscari armeniacum Early to mid-spring N, SW, SC, SE, HA
Hyacinth Hyacithus orientalis Early spring N, SW, SC
Iris Iris spp. Late spring N, SW, SC, SE
Leucojum Leucojum aestivum Mid-springm N, SW, SC, SE
Ornamental Onion Allium spp. Late spring N, SW, SC, SE
Ornithogalum Ornithogalum umbellatum Late spring N, SW, SC
Pink Buttercups Oxalis adenophylla Late spring N, SW, SC
Puschkinia Puschkinia libanotica Mid-spring N, SW, SC, SE, HA
Snowdrops Galanthus nivalis Very early spring N, SW, SC, SE, HA
Squill scilla siberica Early to late spring N, SW, SC, SE, HA
Tulip Tulipa spp. Mid to late spring N, SW, SC, SE, HA
Trout Lily Erythronium spp. Mid-spring N, SW, SC, SE, HA
Winter Aconite Eranthis cilicium Very early spring N, SW, SC, SE, HA

Key to regional adaptation notes:
N = Northern Idaho valley locations in USDA zones 5 & 6, Moscow to Sandpoint.
SE = Southeastern Idaho valley locations in USDA zones 3 & 4 from Rexburg to Pocatello .
SC = South-central Idaho Magic Valley locations in USDA zones 4 & 5, Burley and Twin Falls .
SW = Southwestern Idaho Treasure Valley locations in USDA zones 5 & 6, Boise area (also Lewiston ).
HA = High altitude (>5,000 ft) areas of central, southeastern Idaho and similar locations elsewhere.


lily

Many lily species grow well in Idaho

Summer Flowering Bulbs

Summer bulbs provide color after the spring flowers have stopped blooming. Many of them bridge the gap between spring bulbs and other perennials. Others bloom late into the summer. Summer bulbs are a mixture of those hardy in Idaho and those that are not hardy and must be treated as annuals. Non-hardy bulbs can be unearthed and stored for replanting the next year. Most of the tender summer bulbs are not recommended for planting in the shortest season areas of Idaho because of the potential for frost injury. For more information on storing tender bulbs overwinter, view this North Dakota Extension article.

Common Name
Scientific Name
Relative Bloom Time
Regional Adaptation
Bulbs Hardy in Idaho*
Arum Arum italicum Early Summer N, SW
Brodiaea Brodiaea laxa Early summer N, SW
Foxtail Lily Eremurus spp. Early summer N, SW, SC
Hardy Gladiolus Gladiolus nanus Mid-summer N, SW, SC, SE
Iris Iris spp. Early summer N, SW, SC, SE
Ixiolirion Ixiolirion pallasii Early summer N, SW, SC
Lily Lillium spp. Early to late summer N, SW, SC, SE
Ornamental Onion Alliums spp. Early summer N, SW, SC, SE
Ornithogalum Ornithogalum umbellatum Early summer N, SW, SC
Peonies Paeonia x hybrida Early summer N, SW, SC, SE, HA
Tender Summer Bulbs Grown as Annuals*
Begonia Begonia spp. Mid to late summer N, SW, SC, SE
Canna Canna spp. Late summer N, SW, SC, SE
Caladium Caladium spp. (colorful foliage) N, SW, SC, SE
Dahlia Dahlia spp. Mid-summer N, SW, SC, SE, HA
Gladiola Gladiolus spp. Early summer N, SW, SC, SE, HA

*Hardy summer bulbs can be planted permanently into the garden, tender bulbs must be handled like annuals with the bulbs being harvested and stored indoors during the winter months.

Key to regional adaptation notes:
N = Northern Idaho valley locations in USDA zones 5 & 6, Moscow to Sandpoint.
SE = Southeastern Idaho valley locations in USDA zones 3 & 4 from Rexburg to Pocatello .
SC = South-central Idaho Magic Valley locations in USDA zones 4 & 5, Burley and Twin Falls .
SW = Southwestern Idaho Treasure Valley locations in USDA zones 5 & 6, Boise area (also Lewiston ).
HA = High altitude (>5,000 ft) areas of central, southeastern Idaho and similar locations elsewhere.

Caladiums

Caladiums provide great summer foliage color


Fall Flowering Bulbs

A few bulbs bloom during the fall season. Those listed below are hardy in Idaho and include:

Common Name
Scientific Name
Relative Bloom Time
Regional Adaptation
Colchicum Colchicum autumnalis Late Fall N, SW, SC
Crocus (late types) Crocus spp. Late Fall N, SW, SC, SE
Hardy Cyclamen Cyclamen spp. Mid Fall N, SW, SC, SE
Lily Lillium spp. Mid Fall N, SW, SC, SE

Key to regional adaptation notes:
N = Northern Idaho valley locations in USDA zones 5 & 6, Moscow to Sandpoint.
SE = Southeastern Idaho valley locations in USDA zones 3 & 4 from Rexburg to Pocatello .
SC = South-central Idaho Magic Valley locations in USDA zones 4 & 5, Burley and Twin Falls .
SW = Southwestern Idaho Treasure Valley locations in USDA zones 5 & 6, Boise area (also Lewiston ).
HA = High altitude (>5,000 ft) areas of central, southeastern Idaho and similar locations elsewhere.

Crocus

Some Crocus species bloom in the fall


The International Bulb Society has constructed a picture gallery that includes most of the worlds bulb propagated plants.

A fact sheet from North Carolina State University provides assistance with selection of bulb plants.

 August 17, 2012
Aug 172012
 

Most perennials do not bloom throughout an entire growing season. Knowing the period of bloom will help with determination of plant combinations that provide color all summer long. Below are lists of perennials classified by their flowering time. The dates are approximate and will depend on geographical location. The warmer valleys of Idaho may provide blooming conditions for many plants as much as 6 weeks earlier than the cooler northern or mountainous regions.


Gaillardia

Blanket Flower blooms all summer

Perennials with Extended Blooming Times

These are the exceptional plants that bloom over several months through spring, summer, and fall.

Common Name Scientific Name Regional Adaptation
Anthemis (Dyer’s Chamomile) Anthemis tinctoria N, SW, SC, SE, HA
Aster Aster spp. N, SW, SC, SE, HA
Balloon Flower Platycodon grandiflorus N, SW, SC, SE, HA
Bee Balm Monarda didyma N, SW, SC, SE, HA
Bellflower Campanula spp. N, SW, SC, SE, HA
Blanket Flower Gaillardia . grandiflora N, SW, SC, SE, HA
Butterfly Weed Asclepias tuberose N, SW, SC, SE, HA
Cranesbill Geranium spp. N, SW, SC, SE, HA
Deadnettle Lamium maculatum N, SW, SC, SE, HA
Dianthus Dianthus spp. N, SW, SC, SE, HA
Flax Linum perenne, Linum grandiflorum N, SW, SC, SE, HA
Hollyhock Alcea rosea N, SW, SC, SE, HA
Lavender Lavendula angustifolia SW, SC
Pincushion Flower Scabiosa caucasica N, SW, SC, SE, HA
Potentilla Potentilla verna N, SW, SC, SE, HA
Russian Sage Perovskia atriplicifolia SW, SC
Shasta Daisy Leucanthemum x supermum N, SW, SC, SE, HA
Veronica Veronica spp. N, SW, SC, SE
Yarrow Achillea spp. N, SW, SC, SE, HA

Key to regional adaptation notes:
N = Northern Idaho valley locations in USDA zones 5 & 6, Moscow to Sandpoint.
SE = Southeastern Idaho valley locations in USDA zones 3 & 4 from Rexburg to Pocatello.
SC = South-central Idaho Magic Valley locations in USDA zones 4 & 5, Burley and Twin Falls.
SW = Southwestern Idaho Treasure Valley locations in USDA zones 5 & 6, Boise area (also Lewiston).
HA = High altitude (>5,000 ft) areas of central, southeastern Idaho and similar locations elsewhere.


Poppies

Poppies provide spring color. Courtesy of FreeFoto.com

Early-Blooming Perennials

These are plants that bloom in early spring, typically March (warm areas), April, and May.

Common Name Scientific Name Regional Adaptation
Bleeding Heart Dicentra spp. N, SW, SC, SE, HA
Bloodroot Sanguinaria canadensis N, SW, SC, SE, HA
Blue False Indigo Baptisia australis N, SW, SC, SE, HA
Bugleweed Ajuga reptans N, SW, SC, SE, HA
Candytuft Iberis sempervirens N, SW, SC, SE
Columbine Aquilegia spp. N, SW, SC, SE, HA
Delphinium Delphinium x elatum N, SW, SC, SE, HA
Dianthus Dianthus plumarius N, SW, SC, SE, HA
False Rock Cress Abrietia deltoidea N, SW, SC
Forget-Me-Not Anchusa myosotis N, SW, SC, SE, HA
Gas Plant Dictamnus albus N, SW, SC, SE, HA
Jacob’s Ladder Polemonium reptans N, SW, SC, SE, HA
Mountain Bluet Centaurea montana N, SW, SC, SE
Oriental Poppy Papaver orientalis N, SW, SC, SE, HA
Peony Paeonia spp. N, SW, SC, SE, HA
Phlox, Creeping Phlox subulata N, SW, SC, SE, HA
Prairie Smoke Geum triflorum N, SW, SC, SE, HA
Pussytoes Antennaria dioica N, SW, SC, SE, HA
Rock Cress Arabis caucasica N, SW, SC, SE, HA
Sea Pink (Sand Wort) Armeria maritime N, SW, SC, SE, HA
Snow-in-Summer Cerastium tomentosum N, SW, SC, SE, HA

Key to regional adaptation notes:
N = Northern Idaho valley locations in USDA zones 5 & 6, Moscow to Sandpoint.
SE = Southeastern Idaho valley locations in USDA zones 3 & 4 from Rexburg to Pocatello.
SC = South-central Idaho Magic Valley locations in USDA zones 4 & 5, Burley and Twin Falls.
SW = Southwestern Idaho Treasure Valley locations in USDA zones 5 & 6, Boise area (also Lewiston). HA = High altitude (>5,000 ft) areas of central, southeastern Idaho and similar locations elsewhere.


Asters

One of many summer blooming asters

Mid-Season Perennials

These are plants that bloom during the mid-summer months, typically June, July, and into August.

Common Name Scientific Name Regional Adaptation
Alumroot (Coral Bells) Heuchera sanguinea N, SW, SC, SE, HA
Aster Aster spp. N, SW, SC, SE, HA
Astilbe Astilbe x arendsii N, SW, SC, SE
Bee Balm Monarda didyma N, SW, SC, SE
Bellflower Campanula spp. N, SW, SC, SE, HA
Blanket Flower Gaillardia . grandiflora N, SW, SC, SE, HA
Butterfly Weed Asclepias tuberose N, SW, SC, SE, HA
Cardinal Flower Lobelia cardinalis N, SW, SC, SE, HA
Chrysanthemum Deudranthuna x grandiflora N, SW, SC, SE, HA
Deadnettle Lamium maculatum N, SW, SC, SE, HA
Coreopsis Coreopsis spp. N, SW, SC, SE
Flax Linum perenne N, SW, SC, SE, HA
Foxglove Digitalis purpurea N, SW, SC, SE
Gloriosa Daisy Rudbeckia x hybrida N, SW, SC, SE, HA
Goatsbeard Aruncus dioicus N, SW, SC, SE
Hollyhock Alcea rosea N, SW, SC, SE, HA
Larkspur Delphinium spp. N, SW, SC, SE, HA
Lavendar Lavandula angustifolia SW, SC
Lupine Lupinus spp. N, SW, SC, SE, HA
Penstemon Penstemon spp. N, SW, SC, SE, HA
Phlox Phlox spp. N, SW, SC, SE, HA
Pincushion Flower Scabiosa caucasica N, SW, SC, SE, HA
Red Valerian Centranthus rubber SW, SC
Russian Sage Perovskia atriplicifolia SW, SC
Sage Salvia officinalis N, SW, SC, SE, HA
Shasta Daisy Leucanthemun x superbum N, SW, SC, SE, HA
Silver Mound Artimisia schmidtiana N, SW, SC, SE, HA
Stoke’s Aster Stokesia laevis N, SW, SC, SE, HA
Sundrops (Evening Primrose) Oenothera fruticosa SW, SC, SE
Veronica Veronica spp. N, SW, SC, SE
Yarrow Achillea spp. N, SW, SC, SE, HA

Key to regional adaptation notes:
N = Northern Idaho valley locations in USDA zones 5 & 6, Moscow to Sandpoint.
SE = Southeastern Idaho valley locations in USDA zones 3 & 4 from Rexburg to Pocatello.
SC = South-central Idaho Magic Valley locations in USDA zones 4 & 5, Burley and Twin Falls.
SW = Southwestern Idaho Treasure Valley locations in USDA zones 5 & 6, Boise area (also Lewiston).
HA = High altitude (>5,000 ft) areas of central, southeastern Idaho and similar locations elsewhere.


Sundrops

Fall blooming sundrops or evening primrose

Late-Blooming Perennials

These are plants that bloom in late summer, continuing into fall, many blooming through the earliest frost events. The time period for bloom will typically be August, September, and in warm regions continuing into October.

Common Name Scientific Name Regional Adaptation
Aster Aster spp. N, SW, SC, SE, HA
Chrysanthemum Deudranthuna x grandiflora N, SW, SC, SE, HA
Coreopsis Coreopsis spp. N, SW, SC, SE, HA
Deadnettle Lamium maculatum N, SW, SC, SE, HA
Globe Thistle Echinops ritro N, SW, SC, SE, HA
Gloriosa Daisy Rudbeckia x hybrida N, SW, SC, SE, HA
Leadwort (Plumbago) Cerastostigma plumbagonoides N, SW, SC, SE, HA
Lavendar Lavandula angustifolia SW, SC
Mullein Verbascum spp. SW, SC, SE
Obedient Plant Physostegia virginiana N, SW, SC, SE, HA
Orange Coneflower Rudbeckia fulgida var. sullivantii N, SW, SC, SE
Phlox, Tall Phlox spp. N, SW, SC, SE, HA
Pincushion Flower Scabiosa caucasica N, SW, SC, SE, HA
Purple Coneflower Echinacea purpurea N, SW, SC, SE, HA
Red Hot Poker Kniphofia uvaria SW, SC
Russian Sage Perovskia atriplicifolia SW, SC
Sneezeweed (Helen’s Flower) Helenium autumnale N, SW, SC, SE, HA
Stonecrop Sedum spp. N, SW, SC, SE, HA
Sundrops (Evening Primrose) Oenothera fruticosa SW, SC, SE

Key to regional adaptation notes:
N = Northern Idaho valley locations in USDA zones 5 & 6, Moscow to Sandpoint.
SE = Southeastern Idaho valley locations in USDA zones 3 & 4 from Rexburg to Pocatello.
SC = South-central Idaho Magic Valley locations in USDA zones 4 & 5, Burley and Twin Falls.
SW = Southwestern Idaho Treasure Valley locations in USDA zones 5 & 6, Boise area (also Lewiston). HA = High altitude (>5,000 ft) areas of central, southeastern Idaho and similar locations elsewhere.

 August 17, 2012
Aug 162012
 

During the spring in April to mid May when temperatures are still cool, most cool-season lawns in Idaho will use about one inch of water each week. From about late May to mid August, lawns will use about 2 inches of water per week or slightly more. Then, from mid August to late September they use just over one inch of water. During periods when significant amounts of precipitation is received, lawn sprinklers systems should be turned off. There is no need to irrigate when the soil is already filled to capacity.

Depending on the year and the onset of winter, grasses will still use close to an inch per week in October, and it is important to keep the soil moist, not overly wet, but moist going into winter. This will help prevent winter desiccation damage.

Lawns with significant shade and wind protection will not need as much water, but remember that the grass will be competing with tree roots for water and nutrients, so extra attention needs to be given to these landscapes.

 August 16, 2012
Aug 162012
 

To understand the timing of lawn fertilization, it is important to understand the seasonal growth pattern of a grass plant. In the spring, grasses are coming out of winter dormancy and begin rapid growth using stored energy reserves from last year. Grasses that are over-fertilized with nitrogen in the spring will spend too much of those energy reserves on leaf growth and will not have enough left over to take them through summer’s heat and drought stress. All that is needed in the spring is to supply the grass with just enough nitrogen fertilizer to prevent it from becoming chlorotic (very light green to yellow in color).

As temperatures rise in the summer, leaf and root growth start to slow. Over-fertilization at this time could be very detrimental to the health of the grass and even cause areas to die. Avoid fertilizing during the summer except to prevent chlorosis. Very light applications and use of a slo- release fertilizer will help keep the grass green in the summer without burning or damaging the lawn.

As temperatures cool and hours of light per day diminishes in late summer to early fall, grasses begin preparing for winter by sending their energy reserves to their rhizomes and roots. A fertilizer application at this time will help the plant maximize energy production and most of the engergy will be sent to storage instead of being used for leaf growth.

Table 1 gives recommendations for various grasses at various times of the year. Keep in mind that the March application may be omitted if green-up is satisfactory and a late fall application was made the previous year. In this case, a single application of 1 lb N per 1000 ft2 can be made. Use slow release fertilizers for a late fall application and on sandy soils throughout the year to reduce nitrogen leaching. Additionally, if you are using a mulching mower or otherwise returning clippings to the lawn, you may be able to cut back the nitrogen by about one fourth.

Table 1. Nitrogen fertilization schedule for home lawns.  (Adapted from Colorado State University lawn fertilization extension fact sheet).

Grass Type¹ & Maintenance Level² Mid March – Mid April Early May – Early June July – Early August Mid August – Mid September Early October – Early November
Rates are in lbs of N per 1000 ft2
KBG – Low 1/2 1/2 none 1 1 (optional)
KBG – Med – High 1/2 – 1 1 none 1 1 – 2 (2 is optional)
Tall fescue – Low 1/2 1/2 none 1 1 (optional)
Tall fescue – Med – High 1/2 1 none 1 1 (optional)
Fine fescue – Low 1/2 1/2 none 1/2 none
Fine fescue – Med 1/2 1 none 1 none
Buffalograss none 1/2 – 1 1/2 – 1 none none
¹Grass Type: KBG = Kentucky bluegrass
²Maintenance Level: Low = low maintenance, Med = medium, High = high maintenance
 August 16, 2012
Aug 142012
 

Trees should be fertilized in early spring or mid-fall as long as the soil temperature is above 40º F two inches below the soil surface. Soil should also be moist. Avoid fertilizing in late summer and early fall as a nutrient application at this time could cause unwanted succulent growth that may fail to harden off before fall frosts hit.

Fertilizer Application Methods

Broadcast or topdress – fertilizer is added directly to the soil surface. This method is good for N, which moves readily through the soil, but poor for P and K that move slowly through the soil. Fertilizer should be applied to the drip line and at several foot intervals out from the drip line for mature trees.

Soil incorporated – dry or liquid fertilizer is added to holes in the soil beneath the canopy and extended beyond the drip line and provide a long lasting effect. Holes should be up to 12 inches deep and 1 to 2 inches in diameter and made in concentric circles 2 feet apart around the tree trunk with the first circle no closer than 3 feet from the trunk.

Foliar sprays – best for supply nutrients for plant use in only trace amounts, such as Zn, Mn and Fe.

Tree spikes are a dry soil injection method, with a hardened column or cylinder of fertilizer hammered into the soil.

Controlled release pellets are typically broadcast on the soil surface, but they can also be placed in holes augured into the soil.

Tree spikes and slow release pellets may delay the development of winter hardiness so it is best to use them in late fall or early spring.

 August 14, 2012
Aug 132012
 

Early spring and early fall are the best times of the year to plant because plant shoot growth is minimal and roots have time to become established after planting. Bare root plants should be planted before bud break in March, April or May. Balled and burlapped and container plants can be planted anytime of the year as long as the soil is not frozen. However, early spring or early fall are still considered the best times to install these types of nursery plants.

Where to Plant

Select plants appropriate for the location in which they’ll be planted. Pay attention to the eventual mature height and spread of a tree or shrub, keeping in mind that some community ordinances may restrict planting of trees near power lines, parking strips, street lights, sewers, traffic control signs and signals, sidewalks and property lines.

Other questions to consider are:
  • Will this tree or shrub drop leaves, flowers, or fruit that may be a nuisance to neighbors?
  • Will this plant receive the sufficient amount of sunlight in this location? Will it shade other plants?
  • Will this plant share moisture requirements with the plants surrounding it? Is it compatible?
  • What kind of care, including pruning, will this plant require?

Many of the resources listed here provide information to help homeowners answer these questions.

 August 13, 2012
Aug 132012
 

Selecting the proper time to prune is important. Heavy pruning at the wrong time of year can stimulate unwanted growth or prevent flowering or fruiting. Before pruning, consider time of year, type of plant and flowering periods of certain plants. See the table below.


Time of Year to Prune Various Types of Plants.
Season
Type of plant Fall Winter Spring Summer Comments
Early Late Early Late Early Late Early Late
Deciduous shrubs for shrubs
that flower before
June 1
Deciduous shrubs for shrubs
that flower after
May 30
Deciduous
trees
a
Conifers –
Shrubs and
Trees
All conifers
except for pines
(see below)
a
Pines
a
Broadleaf
evergreen
shrubs
For shrubs grown
for flowers
Broad leaf
evergreen
shrubs
For shrubs grown for foliage (hedge)

When to Prune New Growth on Pines

Pines have buds only at the tip of the branches. If a branch is pruned after a growth flush and the terminal bud is removed, regrowth is impossible. Pine branches should be pruned or pinched in early summer when the new branch (candle) has begun to elongate but before the needle bundles open. This pruning causes the growth to be more compact but still allows buds to form for the following year.

 August 13, 2012
Aug 102012
 

Pest and Disease Management
Fruit Thinning
Fertilization

Healthy and productive fruit trees require regular care throughout the year. A few of the more important tasks are listed here. Click here for links to more complete guidance on fruit tree care.

In early spring before the new leaves appear, examine the trees carefully for signs of damage from winter cold, snow and ice, diseases, girdling or other damage from animals, and signs of pests or pest damage.

Prune your fruit trees. Normally, we prune fruit trees in late winter or early spring before the buds begin swelling. First remove any diseased or damaged wood. Damaged and diseased wood can be pruned out any time of the year. If the branch is or may be diseased, rinse your pruning shears after every cut in a solution of 20% household bleach in water or 70% ethyl or isopropyl alcohol. Do not compost diseased or pest infected branches.

Remove all sprouts arising from the roots and trunk below the graft union. Next, concentrate on building a strong structure that will support the branches and crop. Remove enough wood to maintain an open canopy that allows light to penetrate to the trunk and air to circulate freely through the tree. Most water sprouts come off at this time. Water sprouts are vigorous, vertical shoots that can easily develop into multiple leaders and create a crowded, hard to manage tree. With some crops, pruning can help manage the tree height by removing branches above a desired height. Height management through pruning works well for peaches, nectarines, and apricots. For apples and pears on dwarfing rootstocks, pruning is also valuable for controlling height. Controlling cherry and plum tree height with pruning can be difficult.

 August 10, 2012
Aug 102012
 

Fruit trees need regular fertilization to remain healthy and productive. How much fertilizer to add depends on the nutrients already available in the soil and the size of the trees. Home gardeners tend to over fertilize their trees, which delays or reduces blossom formation, produces poor yields and fruit quality, and results in vigorous growth of branches and leaves and increased pruning.

Large trees, such as apples on seedling rootstocks, require more nutrients than dwarf trees. Commercial fruit growers have laboratories analyze the leaves in mid summer to determine the nutrient status of the tree. For home gardens, start with the amounts in Table 1 below and watch your trees carefully. If a tree that is old enough to bear a crop produces lush shoots and dark green leaves but few blossoms, you are applying too much nitrogen and/or pruning off too much wood. If growth is slow, stunted, or yellowish, add more nitrogen. Apply fertilizers from early spring through the end of June.


Nitrogen Source Nitrogen Content (%) Planting Year Young Trees (rate per year since planting) Mature Trees (six years or more from planting) (lb)
10-10-10 10 0 6 oz 2
16-16-16 16 0 4 oz 1.5
21-0-0 (ammonium sulfate) 21 0 3 oz 1
Dry manure (other then poultry) 1-2 0 3 lbs 15
Dry poultry manure 3-5 0 1 lb 5

 August 10, 2012
Aug 102012
 

The most important tool in managing pests and diseases in your orchard is regular scouting. At least weekly, closely examine the trunks and branches, flowers, leaves, and fruit for signs of pests or diseases. If you are not sure what a problem is or how to control it, get help from your county extension office, nursery or garden center.

Just as the buds are swelling, but before they open in early spring, you may wish to apply a spray of dormant crop oil. Even better is a mix of dormant oil and sulfur. The oil helps control pests by smothering the overwintering pests and eggs. Beneficial insects and mites that feed on these pests usually overwinter elsewhere and are not harmed by the oil. Various sulfur formulations are available to gardeners for dormant applications are very valuable in helping manage fungal diseases. Your garden center can advise you on suitable products. Always follow label directions and regulations carefully. Some dormant oils and sulfur treatments are approved for organic fruit production.

 August 10, 2012
Aug 092012
 
How Do I Transplant Existing Trees?

Do you have a shrub or tree that is planted in the wrong place in your yard? Does your neighbor have a tree that they will let you have, if you move it yourself? Have you wondered how to move a tree and keep it alive? If a tree or shrub is not too big, you can transplant it yourself and save the cost of having it done professionally. Be prepared for some hard work, and take the time to learn how to do it properly. If you work carefully, you can expect a high probability of success in keeping the tree alive and growing after transplanting is complete. The following information will guide you in the transplanting procedure. Recognize that this process can be used for all woody plants, trees, shrubs, or vines. Due to size, trees are the hardest to move, so they will be used as the example

When Should I Transplant?

Transplant early in the spring, after soil frost is gone but before new growth occurs. Once the buds start to break and grow, transplant survival decreases drastically. Plants dug during, or soon after bud break, are intolerant of transplanting especially evergreen trees, but all trees will do better if moved when they are dormant.

What Basic Transplanting Method Should I Use?

Plan to use a ball-and-burlap method for moving a tree. This technique involves moving a large ball of undisturbed soil along with the roots. Keeping soil around the roots is important for survival of trees that have grown unrestricted or unpruned in a yard or landscape situation. The method for digging a root ball will be described in detail below.

How do I Decide if a Tree is Moveable?

The most important consideration for assessing ability to transplant a tree is size. Small trees survive transplanting better than large trees, so the smaller the better. Also, the bigger the tree, the larger the soil ball that should be maintained around roots. A bigger root ball means more weight that must be moved. You must match necessary weight with personal physical ability and tools available for transplanting.

A 24-inch diameter root ball dug to 16 inches deep will weigh anywhere from 200 to 300 pounds, so tree size quickly restricts what is physically possible.

Due simply to the weight involved, it is probably wise to avoid moving trees whose trunks are larger than 2.5 inches in diameter. Alternately, they should simply be cut down or moved with the help of a professional using a mechanical tree spade.

How do I Determine Proper Root Ball Size?

First, figure out the proper diameter for the root ball. As a general rule, for every ONE inch of trunk diameter (measured at 4 inches above the ground), the soil root ball should be 12 inches in diameter. So, if you have a tree whose trunk is 2 inches in diameter at 4 inches above the ground, the root ball should be dug so that it is 24 inches in diameter (with the trunk in the center). Keep in mind that tree height is NOT a factor here. The root ball diameter should be based on the trunk diameter.

Root ball size 1

Diameter less than 20 in. Depth not less than 75% of diameter or 3/4 of width.

Root ball size 2

Diameter 20 to 30 in. Depth not less than 66-2/3% or 2/3 of width.

Root ball size 3

Diameter 31 to 48 in. Depth not less than 60% or 3/5 of width. Balls with a diameter of 30 in. or more should be drum laced.

Next, you will need to decide how deep to dig the root ball for the trees by using the following information:

  • If the root ball diameter < 20 inches: root ball depth should be 75% of the diameter.
  • If the root ball diameter is > 20 inches but < 30 inches: root ball depth should be 66% of the diameter.
Detailed Instructions for Transplanting a Tree
  1. Digging materialsGather tools to complete the transplanting job. A sharp shovel or spade is required. Burlap is used to hold the soil ball together, and nails can be used to “pin” the burlap in place to hold the material on the root ball. Twine can be used to provide extra support to hold the soil ball together. Hand pruners and a sharp pocket knife can be used to prune or cut branches or roots as needed.
  2. Root ball diameterCheck the trunk diameter 4 inches above the ground. Determine the proper root ball diameter and depth using the rules given above. Once you know the diameter then roughly mark a circle of the proper diameter on the ground around the tree with the trunk in the center.
  3. Dig at least one or two inches further out than the mark for the root ball. Use the BACK of the shovel toward the trunk, and push the shovel straight into the ground. Once the shovel sinks into the soil as far as you can comfortably push it, then lift it STRAIGHT OUT of the ground. DO NOT push on the shovel toward the root ball since you can break up the root ball. The idea is to keep the root ball intact without cracking it.
  4. Once you have dug all the way around the trunk by pushing a SHARP shovel into the soil, then you can use the shovel OUTSIDE of your vertical cuts to remove soil. In this way, you are starting to make a vertical cylinder of soil – the root ball – around the trunk. As you remove the soil, avoid putting pressure on the vertical cylinder of soil (here after called the root ball) so that you avoid cracking it. You want the root ball intact.
  5. After removing the excess soil outside of your cut lines, put the BACK of the shovel against the root ball again and dig deeper this time, digging all the way around the root ball and keeping the shovel straight vertically as you dig. Again, avoid putting pressure on the root ball so that you avoid cracking it. After digging deeper all the way around the root ball, remove the soil outside of your cuts so that you have room to dig deeper again.
  6. To make your digging easier, you should probably clear about 8 inches (or more) of soil away from your vertical cuts so that you have room to dig deeper. The more soil you remove to the outside of your cuts, the easier you can dig down, BUT moving that soil out requires plenty of space and your energy to dig it and move it out.
  7. Root ball depthAs you make vertical cuts for the sides of the root ball and dig deeper, you can begin to taper the root ball, perhaps angling your cuts 1 to 2 inches toward the center of the ball for every 12 inches deep that you dig. In this way, you will have a root ball that is wider at the top and tapered to its base. Since you also should have started the root ball a few inches wider than was necessary, you can make vertical cuts to make your root ball smaller while tapering its shape toward the bottom of the ball. As you make the vertical cuts on the soil cylinder/root ball, you may encounter some very thick roots. If your shovel is sharp enough, it should cut the root(s) with a few good hard strokes or pushes. If the root is either too large or your shovel too dull, AVOID continually hitting or slamming the root with the shovel, since this practice causes excess root damage and will probably help break the root ball. Instead, have a sharp pair of loppers (or other sharp pruning tool) with you to cut the root so that you can continue digging after the root is cut.
  8. Once you dig deep enough, based on the depths provided above, you should start to undercut the root ball. This procedure involves using your shovel to make/cut the bottom of the root ball. You will need to cut under the cylinder of soil from the outside, so this procedure is more readily accomplished (but not necessarily easily accomplished) if you removed the soil from a large area outside of the root ball. Undercutting the root ball must be done carefully since you can easily crack the root ball and ruin all your efforts to this point. The goal of undercutting is to cut roots that may be growing vertically (such as the taproot) or close to vertical. To undercut, use the shovel in the regular way (shovel face now toward the tree) and push the blade toward the center of the root ball going around the ball several times. Digging the root ball (soil cylinder) a little deeper than needed (according to the nursery stock standards) will enable you to remove soil – after making some horizontal cuts – at the bottom and ensure that vertical roots are cut. Trying to move the soil ball with a few roots intact under the root ball (particularly the taproot) will nearly always break open the ball.
  9. Once you have dug under the root ball and cut all the roots, you will need to protect the root system so that the soil holds together and the ball does not crack when trying to move the soil. Typically, burlap is used for holding the root ball together, but other types of material can be used as long as the material is strong enough not stretch and break when trying to tie it around the soil ball. You will need different sized squares of material to hold the soil together depending on the ball size. For example, a 24-inch diameter root ball may require a 36-inch by 36-inch square piece of burlap.
  10. Once the root ball is cut free in the bottom of the hole, take the burlap square and fold a corner of it down so that it goes to the bottom of the hole. Fold about one-quarter to one third of the burlap down. Next, the long diagonal (from corner to corner) of the burlap is tied around the root ball, using the burlap as a band to hold the soil in place. If you are unable to tie the material around the root ball, use a larger piece of material. After tying the burlap tightly around the root ball, shift the root ball (carefully) so that you can grab the folded down corner of material and pull it under the root ball. In this way, you will have the material under the root ball and can cover the bottom and sides of the ball. Once you grab the corner of the material and cover the bottom of the ball, you may need to re-tie the material around the root ball. As you complete these procedures, be careful to avoid breaking the root ball.
  11. Once the burlap or supporting material is all around the root ball, you can pull the root ball out of the hole by lifting on the soil root ball NOT the tree trunk. Once the root ball is out of the hole you can shift or re-tie the burlap or supporting material as needed. Usually nursery professionals use pinning nails to make the burlap tight on the ball. Also, for root balls larger than 30 inches in diameter, supporting material, such as twine, wire baskets, or even chicken fencing are recommend for supporting the soil ball since it can break easily.
What do I do next?
  1. The shrub or tree should be replanted to its new location as soon as possible, hopefully within one week. In the mean time, prevent the root ball from drying out and try to keep the roots cool. If the root ball must remain out of the soil for more than a week, consider burying the ball in an organic mulch to retain moisture and reduce the soil temperature.
  2. Finally, plant the tree in its new location. Dig the new planting hole for your tree or shrub to the same depth as the root ball. Do not bury it too deep. See the planting instructions under the Trees, Shrubs, and Vines section of this web site for more details.
 August 9, 2012