starting and growing transplants under lights l.
Skip this Video
Loading SlideShow in 5 Seconds..
Starting and growing transplants under lights PowerPoint Presentation
Download Presentation
Starting and growing transplants under lights

Loading in 2 Seconds...

play fullscreen
1 / 45

Starting and growing transplants under lights - PowerPoint PPT Presentation

  • Uploaded on

Starting and growing transplants under lights Curtis Swift, Ph.D. Colorado State University Extension What it is? Definition – transplanting is the shifting of plants from one place or growing medium to another Goal is to produce vigorous plants ready to be planted in the garden

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Starting and growing transplants under lights' - benjamin

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
starting and growing transplants under lights

Starting and growing transplants under lights

Curtis Swift, Ph.D.

Colorado State University Extension

what it is
What it is?
  • Definition – transplanting is the shifting of plants from one place or growing medium to another
  • Goal is to produce vigorous plants ready to be planted in the garden
why use transplants
Why use transplants
  • Avoid problems of seed emerging through soil crusts of clay soils
  • You can more closely control depth of planting
  • Seeds germinate under ideal conditions
  • Extends the growing season
  • Earlier harvest is more attainable by using transplants than by direct seeding in the field
not all vegetables transplant well
Not All Vegetables Transplant Well
  • Plants difficult or not to transplant include:
    • Root crops (carrots, beets)
    • Leafy biennial herbs (dill)
    • Heading types of Chinese cabbage
    • Cucurbits (cucumbers, pumpkins, squash)
      • Do not like their root systems disturbed
    • Vegetables growing quickly when seeded in the garden (radish, leaf lettuce, spinach)
      • Transplanting is not worth the effort
vegetables traditionally transplanted
Vegetables Traditionally Transplanted
  • Small seed vegetables
    • Tomatoes, peppers, head lettuce, broccoli
  • Some vegetables are traditionally started from transplants because they do not produce seed or the seed lacks vigor
    • Sweet potato, Irish potato
commercially grown transplants
Commercially Grown Transplants


  • They are easy
  • Inexpensive if you only need a few plants
  • They do not require that you commit time and money
  • Better (ideal?) growing conditions and care
commercially grown transplants8
Commercially Grown Transplants


  • It can be difficult to find “good quality transplants”
  • You may not be able to find transplants of a specific cultivar
  • The transplants may introduce diseases, insects, and weeds into your garden
age affects production
Age affects production
  • Smaller, stocky plants that have not started to bloom and/or set fruit will adapt to the garden more easily than leggy transplants that already have small fruits hanging on them.
  • Tomato plants 4-5 weeks old grow and yield better than older transplants.

Best Size – 6 “ tall and 6” wide

producing your own transplants
Producing Your Own Transplants
  • Advantages
    • Can ensure disease-free transplants
    • Transplants available when needed
    • Best use of expensive seed
    • Produces transplants you desire
    • Gives you a good feeling
producing your own transplants12
Producing your own Transplants
  • Problems
    • Low light, excessive nitrogen, and high temperature cause excessive stem elongation
    • Damping off disease
producing your own transplants13
Producing Your Own Transplants
  • Important factors determining your success
    • Growing media
    • Environmental conditions
      • Light
      • Temperature
      • Moisture
producing your own transplants14
Producing Your Own Transplants

Growing Media

  • Want to use a soil-less growing media that does not contain soil from your garden or yard
  • Why not use garden soil?
    • Tends to be poorly drained and subject to water logging
    • Contains insect pests, diseases, and weed seed
producing your own transplants15
Producing Your Own Transplants

Growing Media

  • Characteristics of a good soil-less growing media
    • Free of pests
    • Good water-holding capacity
    • Well aerated and drained
    • Low in soluble salts
producing your own transplants16
Producing Your Own Transplants

Growing Media

  • Common components of a soil-less growing media
    • Peat moss
      • Provides the base for most soil-less media
      • Decayed remains of sphagnum moss
    • Vermiculite
      • Mica-like material that has been heated to a high temperatures
      • Provides pore space and retains moisture and nutrients
    • Perlite
      • An inert light weight volcanic material
  • Plant seeds at a depth of 3 times their diameter
  • Broadcast very small seeds such as broccoli or lettuce and cover with a light sifting of soil
producing your own transplants18
Producing Your Own Transplants


  • Factor most likely to be limiting for good quality transplants
  • Interrelated with temperature and moisture
    • Inadequate light often leads to cold temperatures and too much growth
  • Too little light causes weak spindly plants susceptible to falling over
  • Vegetable transplants need more light than standard houseplants
  • Plants grown in the dark are yellow (chlorotic), taller (etiolated), have thinner stems, and in general, are not so healthy
  • ultra-violet (below 400 nm)
  • visible (approximately 400-700 nm)
  • far-red (approximately 700-800 nm).
producing your own transplants20
Producing Your Own Transplants


  • exposure to red light increases seed germination, reduces seedling stem elongation, and promotes lateral shoot growth of many species
  • an increase in red light and/or a reduction in far-red light in the greenhouse can be used to reduce plant height.
  • Plastic sheeting that reduces far-red light is available and have been used to produce healthier plants.
fluorescent lights
Fluorescent Lights
  • on for 12 to 16 hours per day
  • no more than 4 inches above the tops of the seedlings
  • One cool-white plus one warm-white tube
    • Or
  • Use Full Spectrum Grow Lights

high in red light relative to far-red light, produces short & compact plants.

  • High Pressure Sodium
  • ~$90
  • Expensive
  • Very effective
incandescent lights
Incandescent Lights
  • On for 12 – 16 hours per day
  • 1 to 3 feet from top of plants
  • Spot Grow ~$30
    • Has proper plant growth enhancing light
    • Limited space receives light
  • Regular Incandescent bulb
    • Due to high level far-red light relative to red light, frequently lead to stem elongation.
red vs far red light
Red vs. Far Red Light
  • Controlling the red to far red light ratio is a means of controlling seedling height without reducing fruit yield or quality
  • Incandescent lamps, which are low in R:FR ratio, frequently lead to stem elongation while fluorescent sources, which are high in R:FR ratio, produce short and compact plants.
producing your own transplants25
Producing Your Own Transplants


  • In windows there can often be large temperature fluctuations between day and night or sunny and cloudy days
  • Cooler than optimum temperatures may:
    • Increase disease
    • Cause rough fruit in tomatoes
    • Cause bolting in onions
  • Warmer than optimum temperature may cause weak spindly seedlings
root zone heating
Root Zone Heating
  • Root zone heating is another method to stimulate quick germination
  • Use a heating pad
tomato and pepper air temperature
Tomato and PepperAir Temperature
  • Start seeds at 65 - 75 degrees F.After emergence, lower temperature to 60 - 65 degrees F.
    • Day temperature can be about 10 degrees warmer than night temperature.
    • Do not allow to get too hot
      • 75 - 80 degrees F. is too hot
  • Too high a temperature will result in leggy plants.
cabbage broccoli and cauliflower air temperature
Cabbage, Broccoli, and Cauliflower Air Temperature
  • Seeds should be started at 55 - 60 degrees F.
  • After emergence:
    • Day 65F
    • Night 55 F
producing your own transplants29
Producing Your Own Transplants


  • Avoid cool temperatures and dark conditions
    • Reduces transpiration and increases excess water problems
    • Too much water is associated with diseases which require moisture
      • Examples: root rot and leaf spot fungi
  • Moisture
    • Ways to avoid problems with diseases fostered by too much water
      • Thoroughly water when seed
      • After emergence water in the morning so leaves will be dry before night and spot water only the dry places
  • Too little water rapidly kills young seedlings
if reusing trays or flats
If reusing trays or flats
  • wash to remove any soil or plug media that may adhere to the plastic
  • dip in a 10% solution of chlorine bleach
    • 9 parts water to 1 part bleach
  • rinse trays thoroughly before they

are reused

  • Seedlings will need to be fertilized as soon as they emerge.
  • Avoid fertilizers with a high concentration of urea.
  • Over fertilizing can injure seedlings or promote damping-off disease.
  • Fertilize two to three times per week with the liquid solution.
  • Tomatoes are very responsive to fertilizer and excess fertility will reduce transplant quality.
    • At every watering use a fertilizer concentration of 50 to 100 ppm Nitrogen
    • Or once every seven days - use a concentration of 250 to 350 ppm Nitrogen
  • Peppers require more fertilizer than tomatoes
    • If feeding at every watering, use approximately 100 PPM Nitrogen
    • Increase the concentration if feeding less often.
vining crops
Vining Crops
  • Two to four applications of fertilizer at weekly intervals, at a 100 to 150 PPM Nitrogen concentration, should be sufficient to produce good-quality vine crop transplants.
determining ppm n liquid products
Determining ppm NLiquid Products
  • You need to know ppm N of the product
    • May be ppm on the label
    • May be given as percentage
  • If percentage
    • Base ppm on one gallon
    • One gallon is 3,780 milliliters (ml)
      • Round off to 3,800 ml
determining ppm n liquid product
Determining ppm NLiquid Product
    • i.e. 10% is 100,000 ppm
    • i.e. 12% is 120,000 ppm
    • i.e. 15% is 150,000 ppm
  • Need to dilute to appropriate ppm for final fertilizer solution
determining ppm
Determining ppm

Ci x Vi = Cf x Vf

i = initial

f = final

C = ppm

V = volume in milliliter

1 gallon = 3,800 ml; 1 quart = 950 ml

1 pint = 475 ml; 1 cup = 240 ml

determining ppm40
Determining ppm

Ci x Vi = Cf x Vf

If using a 12% N product (120,000 ppm) and want a 100 ppm final solution:

(120,000 ppm)(Volume in ml) = (100 ppm)(3,800 ml) = ml of product to add to sufficient water to make a gallon of fertilizer with 100 ppm of Nitrogen

1 gallon = 3,800 ml; 1 quart = 950 ml

1 pint = 475 ml; 1 cup = 240 ml

determining ppm for 100 ppm solution c i x v i c f x v f
Determining ppmfor 100 ppm solution Ci x Vi = Cf x Vf

ml to add to water to make one gallon of a 100 ppm N fertilizer solution

10% 100,000 ppm use 3.8 ml

12% 120,00 ppm use 3.2 ml

15% 150,000 ppm use 2.5 ml

20% 200,000 ppm use 1.9 ml

determing ppm of dry fertilizer
Determing ppm of dry fertilizer
  • Add equal amounts of fertilizer to water
    • Add water first
    • Add fertilizer to double the amount in the container
  • The resulting solution is one-half the % on the label of the dry product
    • i.e. 20% N is not 10% nitrogen
    • Do computations using Ci x Vi = Cf x Vf
hardening off transplants
Hardening-off Transplants
  • Definition: Hardening-off is the process whereby transplants stop growth and develop greater tolerance to the weather so they can survive being planted into the garden
  • Is critical for both commercially grown transplants and transplants that you grow on your own
hardening off transplants44
Hardening-off Transplants
  • Hardening-off causes:
    • A slowing of growth
    • Greater cuticle thickness and waxes on leaves
    • Build-up of sugars
  • Ways to harden-off transplants
    • Only water the transplants when they start wilting
    • Stop fertilizing
    • Expose transplants to cool temperatures and/or higher levels of sunlight