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Aug 172012

Four options exist for starting perennial plants. They are:

  1. direct seeding,
  2. indoor production of transplants from seed,
  3. purchasing and transplanting, and
  4. obtaining starts from existing plants.
Direct Seeding

Though the majority of perennials are vegetatively propagated to preserve trueness-to-type, some perennial plants may be grown from seed. Planting seed is the simplest and cheapest propagation method. The advantages of direct seeding are offset by the tendency for plants to be slow and erratic with respect to emergence and early growth. These are usually a problem only in the first year, during which they may delay flowering and shorten the color display of the bloom period.

Plant seed in shallow trenches and cover lightly. Plant extra seed and thin after emergence, if necessary. Refer to the seed package to determine seeding rate. Maintain good moisture at the soil surface by misting lightly until the plants emerge. Once plants are established, deeper irrigation should be applied only after the top 1-2 in. of the soil surface dries out.

Transplanting perennial seedlings into a well-prepared bed

Transplanting perennial seedlings into a well-prepared bed

Indoor Seeding and Transplanting

Growing your own transplants has the best features of both direct seeding and purchase of transplants. However, it has the same limitations of availability as direct seeding. The key to success is providing appropriate conditions for germination and early growth of the new seedlings. Soil, temperature, light, and moisture are the most important elements. The soil medium must be free of disease organisms that may cause death of germinating plants. The best soil medium is a commercial potting soil. Containers may range from recycled plastic pots, paper cups, or commercial seed plug trays. Wash and disinfect all containers before using. Temperatures should be warm enough to allow germination (e.g. 60-75 F during the day and slightly cooler at night).

Unless a greenhouse is available, artificial lighting will be required. Even a south facing window does not supply young plants with enough light to keep them from getting ‘leggy’ and weak. Some seedlings may need as much as 18 hours of light each day to remain healthy. Fancy equipment and expensive “grow lights” are not necessary. A standard fluorescent shop light, easily found at home improvement and hardware stores, fitted with one “warm,” and one “cool” tube works very well. Suspend the light fixture 12-18 inches from the plants and raise as growth occurs. It is also important to keep water availability balanced between too wet and too dry. This requires frequent, light irrigations.

Before transplanting, seedlings should be hardened off. This refers to the procedure of adapting the plants to outdoor conditions to reduce transplant shock. This can be done by placing the plants outdoors in full sun for increasing amounts of time each day for the last week or ten days before planting. Hardening the plants will improve survival and increase the early growth rate. The process of transplanting self-produced plants is identical to that described below for purchased plants.

Purchasing Plants

Buying established plants is the most common method of obtaining perennial plants. It is also the most expensive, but transplants will result in quicker establishment and a longer flowering period during the first year.

When choosing transplants, it is best to buy from a nursery or garden store with personnel knowledgeable about local growing conditions. This will assure availability of adapted species and varieties. Do not look for the largest plants, or necessarily, those that are in bloom. You want the perennial to spend it’s bloom period in your garden, not in the nursery! Seek plants with good dark green color, healthy root systems, and no sign of disease or pest problems. Try to find plants that have been hardened off, in order to aid the transition to the yard.

For most perennial plants, timing of transplanting should correspond with a date one week later than the last frost in your region. Even though some perennial seedlings will withstand relatively hard frosts, there is little advantage to early planting given the longevity of these plants. To estimate the last frost date in your area, look at the Idaho chart compiled by Ed Hume Seeds.

It is best to transplant on a cool, cloudy day with little wind. This will allow acclimation under conditions of limited water loss. After removing a plant from its container, tease roots away from the surface of the root ball. Don’t plant the seedlings too deep. Bury the root ball in a hole sufficiently deep only to bring the soil slightly above the pot soil level. Space the plants according to the instruction on the seed packet or nursery pot label. For the first 7-10 days, water the plants frequently and lightly. For the first few days, the root ball holds all of the roots and is the only source of water. The root ball will need to be wetted as often as it would in the pot until the roots can become established in the surrounding soil.

Frequent, light watering is needed after transplanting. Courtesy of FreeFoto.com

Frequent, light watering is needed after transplanting. Courtesy of FreeFoto.com

Obtaining Starts

Depending on the species, vegetative propagation of perennials is probably the most common method commercial growers use for starting new plants. Homeowners can take advantage of propagation techniques to obtain starts of flowers already in place in their own yard and other places. This requires permission from the owner and a little extra work, but may require no purchase.

A few precautions are needed before trying to propagate a perennial plant. First, it is important to inspect the source plant to make sure it is healthy and free of visible disease. Then it is important to obtain adequate knowledge of the best methods and procedures for propagation of the species of interest, including the proper time of year. Here is a description of the most commonly used propagation methods:

Division – Many perennial plants develop a large multiple crown as they age. These can be cut into two or more pieces to create new plants. This can be done by digging up the plant, dividing into pieces, then replanting each one, or by using a sharp spade to cut a portion from a plant left in place, then replanting the removed segment. This latter method minimizes disturbance of the original plant. Perennials commonly divided include Shasta daisies, phlox, daylilies, iris and chrysanthemums.

Stem Cuttings – Some perennials easily grow roots on stems cut from growing plants, allowing the production of new plants. This method is commonly used by nurseries in lieu of planting seed. Stem cutting is usually done indoors and involves removing a stem tip or middle piece of a healthy, green shoot and poking it into sterile, moist growing medium. The new cutting should be kept out of direct sun and covered with clear plastic (plastic cups work well if only a few cuttings are being rooted) to prevent moisture loss. It usually takes 2-3 weeks for cuttings to develop new roots and several more weeks to be ready to transplant. Many soft-stemmed perennials can be successfully stem cut.

Root Cuttings – Perennials with thick, fleshy roots can be propagated by removing a portion of root and replanting in a new location. It is done by simply digging up a portion of root, cutting it into segments, and replanting each piece. Usually, the larger the root cutting the faster a new plant grows and blooms. Root cuttings, as a rule, should be taken when plants are dormant. Perennials that usually respond well to root cutting include peony, baby’s breath, and bleeding heart.

Layering – Some perennials that vine or have long, flexible stems can be layered, This involves bending a stem to lay along the ground, then covering a middle portion with moist soil (use a pot if the plant will be moved a long distance), leaving the tip uncovered. The covered part of the stem will grow roots, after which the stem can be severed from the original, thus creating a new plant. The rooting process may be helped by scratching or gouging the stem on or below the portion that will be covered. Perennial vines can usually be successfully layered.

In his web site, Dr. Leonard Perry, University of Vermont, provides information on the best method for propagating individual perennial species.

 August 17, 2012
Aug 162012

The most important part of establishing a lawn is proper soil preparation. One of the main reasons for turfgrass failure is a poorly prepared site with inadequate soil characteristics. New construction in subdivisions requires removal of topsoil to allow contouring for adequate storm water drainage. Too often topsoil is not placed back around homes prior to lawn installation. Understanding the requirements of good seedbed preparation will help the long term success of a lawn.

Using good quality seed is also very important. Read the section on turfgrass selection to choose the correct type of grass for your application. Additionally, make sure to purchase seed that has a high germination rate (85% minimum) and contains minimal weed seed and “other crop seed.”

The best time to seed cool-season grasses in Idaho is late summer and fall for several reasons. Soil temperatures are optimum for seed germination, there is less competition from summer annual weeds, and the newly emerged grass seedlings will not be exposed to summer heat. It is possible to seed a lawn successfully in the spring, but extra care will be needed to help the seedlings along during the hot summer temperatures.

The establishment process includes: Site preparation/rough grading, seedbed preparation, seeding/sodding, post seeding/sodding care.

 August 16, 2012
Aug 162012

New home site being prepared for seeding. Note the rock and debris piles to be removed.

Remove rocks and debris from area to be seeded.

Large pieces of leftover construction lumber or tree stumps that are covered with soil will eventually decompose leaving depressions in the lawn and can also lead to the fungus that causes fairy ring. Grade the area sloping away from house foundation at a minimum of 2% (¼ inch fall for every 12 inch run) to allow for adequate drainage of water. At this point in the process is a good time to install an underground irrigation system. However, before installing the system, be sure you know where your landscape features such as trees and flowerbeds will be located so the trees will not later interfere with the irrigation system or the flowerbeds will be properly watered. Before planting a lawn is also a good time to control deep-rooted perennial weeds such as quackgrass, Canada thistle and field bindweed.

After properly grading the subsoil, top soil should be added if not already in adequate amounts on the site (minimum of 6 inches). The final topsoil grade should match the contour of the underlying subgrade.

Seedbed Preparation

Add soil amendments such as compost if the soil is low in organic matter. A soil test will tell you whether the soil requires organic matter or other nutrients. Incorporate the fertilizer and soil amendments to a depth of at least 6 inches.

After the tillage operation, smooth the surface with a rake for smaller areas or drag a piece of chain-link fence behind a riding mower or four-wheeler for larger areas. The final seedbed should be moist, slightly firm leaving a one-quarter inch footprint. During this final raking operation, spread a starter fertilizer and rake into the area. A general rule of thumb is to add a starter fertilizer with adequate phosphorus at a rate of 1 lb nitrogen per 1000 ft².


Seed the area in two directions to ensure adequate coverage, then rake lightly to place the seed at about a one-quarter inch depth. A metal leaf rake works well. Lightly roll the entire area to ensure good seed-to-soil contact using a lightweight roller. Apply a straw mulch, especially on sloped areas, to prevent erosion and help retain moisture as well as buffer temperatures while the seedlings are emerging. It is not necessary to rake away the mulch after emergence if it was applied at the proper rate.

Post Planting Care

Irrigate the area lightly and frequently to keep the surface moist during the germination process. This may require two to three light waterings each day especially during periods of hot, dry weather. A mid morning irrigation and one at mid afternoon may be enough to keep the surface moist, but an additional irrigation may be needed in the early evening as well. Once the seedlings have grown to a height of 1 inch, the irrigations can become less frequent and the amount of water applied can be increased.

The first mowing should be when the seedlings reach just past the desired mowing height. Do not apply any herbicide to the new seeding until the grass has been mowed at least four times. If seeding was done in the fall, a herbicide application could be skipped since all annual weeds will die during the winter. If perennial broadleaf weeds are seen in the fall, they should be controlled, but still wait the minimum 4 mowings before applying a herbicide.


The seedbed should be prepared the same way for sod as for seed. It is also very important that the soil be moist (not wet) at the time of installation to encourage root growth. Sod that is placed on dry soil will have a difficult time growing new roots. Lay sod pieces in a brick-like pattern with edges placed tightly against each other. On sloped areas, place the sod horizontally across the slope and use stakes for steep areas to avoid slippage. Working in long straight lines will help reduce labor and waste. Roll the area lightly after installation to remove air pockets and provide good root-to-soil contact.

Newly sodded areas need frequent irrigation because the grass lacks a root system. An initial irrigation of about one-half to 1 inch should be applied, followed by enough water to keep the soil below the sod moist on a daily basis. For about the first two weeks while the roots are growing, keep checking the soil moisture by lifting up a corner of sod to ensure adequate moisture is present. Avoid traffic on the area for at least 4 weeks to ensure adequate root growth. Sometime during the first year following establishment, a newly sodded lawn should be core aerified to help eliminate any soil layers created between the soil on the sod and the seedbed. Soil layers make it difficult for water and nutrients to move properly throughout the soil profile.

More information about starting a lawn can be found here.

 August 16, 2012
Aug 162012

Most pre-packaged seed you buy in a store will be either a mixture of several types of grasses (Kentucky bluegrass + perennial ryegrass) or a blend of several varieties of one type of grass (Kentucky bluegrass: ‘Baron’ + ‘Chateau’ + ‘Courtyard’).

Mixtures are designed to take advantage of the characteristics of several types of grasses for use in areas with varying conditions. The most common example of a mixture is a sun/shade mix. This type of seed mixture may contain Kentucky bluegrass and creeping red fescue. In sunny locations, the Kentucky bluegrass will thrive and dominate the stand, while in shaded areas the fine fescue will dominate. Perennial ryegrass is commonly added to sun/shade mixtures as a nursegrass since it germinates rapidly and provides protection for the slower emerging grasses. The percentage of perennial ryegrass in a mixture should be less than 20% so that it does not overwhelm the other grasses. Blends of several varieties of one type of grass are designed to take advantage of the desirable characteristics of each variety, for example, disease resistance. There are hundreds of varieties available for each of the grass types and blending several of these together helps guard against diseases as well as increases the environmental adaptation of the grass. Make sure to check the label when purchasing blends and avoid buying those with ‘variety not stated’ since these tend to be older, out-dated varieties.

Seed Sources

Many nurseries and home garden centers provide grass seed. A listing of nursery members of the Idaho Nursery and Landscape Association can be found at their website: www.inlagrow.org/locate.htm

Sod Sources

Click here to find where to buy sod.

 August 16, 2012
Aug 102012
Choosing Vegetable Seed

Choose seed from a reputable seed company. Carefully select varieties that are adapted to local conditions. Proper variety selection can mean the difference between success and failure in the garden. If you are unfamiliar with varieties that grow well in your locale, ask other successful gardeners, local nurserymen, or a county educator.

For more information about vegetable varieties suitable for growing in Idaho, see the UI publication: Choosing and Growing Adapted Vegetable Varieties
For more additional pertinent information, see the Utah State University publication: Home Vegetable Garden Variety Recommendations for Utah

Planting Vegetable Seeds Outdoors

In order to germinate properly, seed must be planted at the right depth and remain moist. As a general rule, vegetable seeds should be covered about three times their lateral diameter (their width, not their length). However, there are exceptions and directions are usually given on the seed envelope. Shallow-planted seed may be covered with clear plastic film (such as plastic food wrap) or wet burlap to raise the soil temperatures and hold the moisture. The covering material should be removed immediately after emergence to prevent burning or abnormal growth of the new plants.

Deciding when to plant seeds can be confusing because optimal planting times vary from crop to crop. The first step in deciding when to plant is to determine the average last frost date for your area. This date can be found in many publications, web sites, or from your local Extension Office. Ed Hume Seeds company maintains a web site with average last frost dates for many locations in Idaho.

Next step is to schedule planting based on the frost-hardiness of each crop. See the accompanying chart for suggestions on planting times of common vegetables.

Planting times

Once planted, it is imperative that good soil moisture is maintained until the plants begin to emerge. In some years, spring rain and cool weather may make irrigation unnecessary. However, in most years, frequent (up to 2 times a day for the crops seeded shallow and every two or three days for the crops seeded deep), light watering may be required to get the seed off to a good start.

Producing and Establishing Transplants

Transplanting is the process of placing partially grown plants, rather than seed, into the garden. Many vegetable crops benefit from being transplanted rather than direct-seeded into the soil. Transplanting makes weed control simpler, enhances the growth and quality of crops that prefer cool, spring weather (such as broccoli and cauliflower), shortens the time to harvest of many fruit-bearing crops (such as peppers and tomatoes), and allows us to grow many crops that are marginally adapted to short-season climates (such as melons).

Vegetables vary in their response to transplanting. Some are very difficult, others transplant well only if proper precautions are followed, others transplant very easily. See the accompanying table for a listing of vegetables that can be successfully transplanted.

Relative ease of transplanting for common vegetables
Appropriate for transplanting and easy to handle Appropriate for transplanting but require extra care for success Inappropriate for transplanting or do not easily survive the process
Broccoli Celery Bean
Brussel sprouts Cantaloupe* Beet**
Cabbage Corn Carrot**
Cauliflower Cucumber* Pea
Chinese cabbage Pumpkin* Radish**
Eggplant Squash* Rutabaga**
Collard Swiss chard Spinach
Leek Watermelon* Turnip**


*The vine crops (cucumber, melons, squash, pumpkin) should be transplanted when seedlings are very young (one or two true leaves) and very vigorous. They should be covered and protected from wind and sunburn for about two weeks after transplanting.
**The root crops (beet, carrot, radish, rutabaga, turnip) are easy to transplant but the roots will branch or have other quality problems as a result of root disturbance.

Transplants can be either purchased or grown at home from seed. Growing your own transplants provides some unique advantages such as increasing the availability of unusual varieties, reducing overall cost, and controlling growth so the plants are the right size when you are ready to plant. In spite of the advantages, growing transplants without good greenhouse facilities can be a challenge.

The most important factors for producing healthy transplants are light, soil mix, irrigation, proper size and growth stage, and hardening. During production, more homegrown seedlings are lost to inadequate light than to any other factor. Vegetable seedlings grown under low light conditions are likely to be spindly and weak. They frequently damp-off (a disease that causes young seedlings to tip over and die). If they survive the early growth phase, these plants are often too tender to survive the move outside into the garden. For these reasons, transplants should be grown under conditions that include or mimic full daylight for at least 10 hours each day.

closeup of leafy green plants and soilIf you do not have a sunny room or back porch with a southern exposure, you will need supplemental lights. Grow-lights are available that supply a good spectrum of light to the plants. The lights should be mounted right over and nearly touching the plants.

It is best to use a soilless planting media containing peat to start seedlings. Soilless mixes are usually free of disease organisms that can cause damping-off. They also hold a large amount of water and maintain the integrity of the rootball when it comes time to transplant. Potting soil can be purchased premixed or you can mix your own soilless media if you prefer; 50 percent vermiculite or perlite and 50 percent fine sphagnum peat (plus a little fertilizer) is excellent for starting seeds.

Timing seed planting to begin transplant production can be a little tricky. Two pieces of information are needed to plan a planting schedule for vegetable transplants. One is the number of days needed to produce an appropriate-sized transplant (see the accompanying table). The other is the date the transplants will be taken to the garden. This can be calculated by knowing the last average frost date for you locale. The cole crops (cabbage, broccoli, cauliflower, kale, brussel sprouts, etc.) and onions can be transplanted 2 to 3 weeks before the last average frost. Most of the salad crops (lettuce, Swiss chard, spinach, etc.) should be transplanted a week or so prior to the last average frost. The tender crops (tomatoes, peppers, eggplants, squash, melons, etc.) should not be transplanted until about one or two weeks after the last average frost and only then if the weather forecast is for reasonably warm and stable conditions. If appropriate protective measures (hot caps, row covers, etc.) are used, the transplant dates can sometimes be earlier by a week or two.

About a week before the transplants are scheduled to go to the garden, they should be “hardened-off”. This is a process of slowly adapting the plants to outside conditions and is necessary for reducing transplant shock and frequency of death. Harden off the plants over a one-week period by moving them outdoors for increasing amounts of time, starting with less than an hour and eventually leaving them outside for much of the day. Move the transplants indoors at night (unless it is forecast to be a warm night) and during inclement weather (especially if it is windy). Water use of the transplants will increase while they are outside, so irrigate accordingly.

Number of weeks required to produce transplants from seed for commonly transplanted vegetable crops
Crop Weeks to produce a transplant from seed*
Broccoli 5 to 7
Brussel sprouts 5 to 7
Cabbage 5 to 7
Cantaloupe 3 to 4
Cauliflower 5 to 7
Celery 8 to 10
Collard 5 to 7
Corn, sweet 3 to 4
Cucumber 3 to 4
Eggplant 6 to 8
Endive 4 to 8
Kohlrabi 5 to 7
Leek 4 to 6
Lettuce 3 to 5
Onion 6 to 8
Parsley 6 to 8
Pepper 6 to 8
Pumpkin 3 to 4
Squash 3 to 4
Tomato 5 to 9

*The number of weeks needed to produce a transplant is based on growth at near room temperature.

Here are a few additional tips for successfully transplanting vegetables into the garden:

Soil Preparation

Have garden soil prepared before transplanting. All additives that require time to break down, such as aged manures, sulfur, limestone, rock fertilizers, and green manures, should be incorporated during the prior fall, or at least several weeks before planting.

Weather Conditions

Transplant on an overcast day, in late afternoon, or in early evening to prevent or reduce wilting. Be sure to water the potted plants thoroughly just prior to transplanting.


Handle plants carefully. Avoid disturbing the roots or bruising the stems.

covered raised bedPlanting

Dig a hole large enough to hold the roots of the plants. Set vegetable plants only very slightly deeper than previously planted. Tomatoes are an exception. They will develop roots all along the stems, and you can plant deeply enough to leave only two or three sets of leaves exposed. Press soil lightly around the roots of transplants and thoroughly water them in. Pour a cup of liquid starter fertilizer solution around each plant, mixed at about ½ of the concentration recommended on the label.


Protect plants from wind and sun for a few days after transplanting by placing newspaper or cardboard on the south side of the plant, or by covering them with commercially available devices, milk jugs, baskets, or up-side-down flower pots (opaque plastic so the sun can get in).


Water the plants once or twice each day for about one week. Then schedule watering two or three times over the next week before going to a normal irrigation routine. Overwatering can cause transplants to suffer from root rots, so don’t overdo it.

 August 10, 2012