BP-31, Ornamental Diseases (2024)

BP-31-W

Ornamental Diseases

Purdue University

Cooperative Extension Service

West Lafayette, IN 47907

Paul C. Pecknold, Extension Plant Pathologist*

Transplant shock is a term that refers to a number of stressesoccurring in recently transplanted trees and shrubs. It involvesfailure of the plant to root well, consequently the plant becomespoorly established in the landscape. New transplants do not haveextensive root systems, and they are frequently stressed by lack ofsufficient water. Plants suffering from water stress may be moresusceptible to injury from other causes such as the weather, insects,or disease. When several stresses are being experienced, the plantmay no longer be able to function properly.

Symptom

Leaf scorch is a common symptom of transplant shock. Leaf scorchfirst appears as a yellowing or bronzing of tissue between the veinsor along the margins of leaves of deciduous plants (those that losetheir leaves in winter). Later, the discolored tissue dries out andturns brown. Other symptoms of transplant shock appear as wiltingleaves (especially on recent transplants), yellowing, and leaf rollingor curling. On needled evergreens, the first symptom of water stressis an overall grey-green coloration to the foliage; with further waterstress, the ends of the needles often turn a light tan color. Ifstress is not alleviated, leaf death occurs and may be followed bytwig and limb dieback.

Overall plant growth is greatly reduced, which is reflected inthe length of the new growth. Poorly growing plants have extremelyshortened internodes, resulting in shortened branch tips relative tothose of an unstressed plant. New leaves or needles of a stressedplant are smaller than normal. It is not unusual for transplants tohave very reduced growth the first year after planting; however,symptoms may be evident for two or more years.

This plant was not watered sufficiently after transplanting.

Factors Contributing to Poor Plant Establishment

Often plants do not become established because they have a pooror injured root system. Bare root trees and shrubs are mostsusceptible to transplant shock. Such "stressed" plants are veryfragile and are more susceptible to other stress factors.

Improper planting. One of the most common causes of plant rootfailure is "wet feet" caused by improper soil amendments--the "bathtubeffect." When planting in heavy soil, be sure to use the same heavysoil to fill the planting hole. Many gardening books suggest addingpeat moss or other amendments to the back fill. This is notrecommended. A light soil mix placed where it is surrounded by heavysoil too often results in trapped water, suffocated roots, andeventually a dead plant.

Planting depth is important. Deep planting results in suffocatedroots while shallow planting causes root stress from the more extremetemperature and moisture fluctuations in shallow soil. Refer toPurdue publication HO-100 for recommended planting depths whenplanting in heavy or sandy soils.

HO-100

Problems can result from failure to spread roots of containergrown plants. Such plants often have roots that are coiled around theinside of the pot. Gently uncoil and spread the roots apart beforeplanting. If this is not done, circling roots can eventually girdleor strangle the trunk as the roots increase in diameter with growth.

Always remove twine, rope, or wire from the trunk at plantingtime to prevent strangulation of the tree as it grows.

Improper watering. Proper watering after transplanting isespecially critical in the first year; over watering is just asinjurious as under watering. Soil type and amount of rainfall willdetermine the frequency and amount of water needed. During thegrowing season, landscape plants in well-drained soils should receiveat least one inch of water per week. Plants in poorly drained soilswill require less frequent watering. Use a garden sprinkler or soakerhose and measure the amount of water applied; use a container withstraight sides.

Improper plant material. Consider the suitability of the plantto its intended site and geographic area. Select species that growbest under the prevailing conditions: wet or dry, acid or alkaline.For example, planting an acid-loving plant such as pin oak in alkalinesoils is asking for trouble. Also consider the plant hardiness zoneyou live in and select plants adapted to that zone. Ask at the gardencenter or nursery if you are unsure which plants are best suited foryour area.

How to Help Your Plants Become Established

1. Select the proper plant for the proper location.

2. Inspect plants before purchase; look for vigorous growth and good color. Ask the sales clerk to knock the plant out of its container to inspect for abundant, healthy, white roots. If only a few, blackened, mushy roots are evident, choose another plant.

3. Plant the material correctly and provide adequate care for several years after planting. Water during dry periods, but be sure not to over water.

4. Don't be impatient if the plant does not take off within the first 12 months. It takes a few years for woody plants to settle in and become established in the landscape.

What to do About Dead or Dying Plants

If your plant dies, try to determine what caused the decline ofthe plant: Not enough water? Too much? Plant not hardy to the region?Correct the problem before replanting with the same plant in the samespot.

Related Publications

For additional information, refer to:

* With assistance from B. Rosie Lerner and Philip Carpenter.TXTEND

Reference to products in this publication is not intended to be anendorsem*nt to the exclusion of others which may be similar. Personsusing such products assume responsibility for their use in accordancewith current label directions of the manufacturer.

REVISED 5/01

It is the policy of the Purdue University Cooperative Extension Service, David C. Petritz, Director, that all persons shall have equal opportunity and access to its programs and facilities without regard to race, color, sex, religion, national origin, age, marital status, parental status, sexual orientation, or disability.

Purdue University is an Affirmative Action employer.

This material may be available in alternative formats.

1-888-EXT-INFO

http://www. extension.purdue.edu/extmedia