Flower Garden - Tips on Growing Ageratum From Seed

Stage 1 Radical  (Embryonic Root)

Sow Indoors:

• Germination 4-10 days.
• Keep media moist and near saturation by watering before placement of seed.
• Press the seed lightly in soil and cover lightly, as the seed does not need light for germination.
• The germination temperature at this stage should be 72 to 75ºF (22 to 24ºC).
• Light levels at 100 to 400 fc (foot candles) will enhance the germination process.
• Soil pH should be 5.5 to 6.2 with soluble salts (EC of .50-0.75 ).  It is important to keep ammonium levels less than 10 ppm. (parts per million)
• Maintain 95 – 97% relative humidity during this time.

Stage 2 Hypocotyls (Stem and cotyledon emergence)

Time of emergence 10-14 days.

• First start reducing moisture levels once the radical emergence occurs. At this point allow the soil to dry out slightly before watering again, this will aids in the germination and rooting process.
• The temperatures at this point should be  68 to 75ºF (20 to 24ºC).
• The soil pH at 5.5 to 6.2 with soluble salts ( EC  of .50-.075).
• Keep light levels high during this time period and keep temperatures in control.

Stage 3 Cotyledon (Growth and development of  true leaves)

Timing of this growth 14-21 days.

• Maintain the soil pH at 5.5 to 6.2 with the soluble salts ( EC .75-1.00)
• You can increase the feed at this point to 50 ppm N- using a complete balanced fertilizer. Increase the nitrogen concentration to 100ppm after a week and continue with this program until you are ready to transplant.
• It is important to alternate your fertilizing feed schedule with every 2 -3 clear water irrigations. Do not allow plants to wilt, as this will cause drought stress and burn the leaves
• The temperature for days should be between 65-72ºF (18-22ºC).
• Keep light levels high during this time period and keep temperatures in control. This will help in the production of producing a well branched plant.
• Ageratum are very sensitive to high salts so do not overfeed.

Stage 4 Getting ready for transplant/growing on period

• Do allow the soil to dry thoroughly; however do not to allow the plants to wilt.
• Keep your temperatures maintained at for Days at 70-80ºF (21-27ºC) and for nights at 58-62ºF (14-17ºC)< li>
• Maintain the soil pH at 5.8 to 6.2 with the soluble salts ( EC between 1.5-2.50)
• You can continue to fertilize at a  feed level at 150 to 200ppm N with a complete balanced fertilizer as needed, however the pH and the EC must be maintained as stated.
• Ageratum do not require a high feed level; they prefer a low to moderate level.  By having excessive amounts of feed your result will be lush and vegetative stretched seedlings. This is what you do NOT want.
• A good option would be to have a low feed program without having any salt accumulation for the plant.

For the growing on to finish stage:

• Night temperature: 58-62ºF (14-17ºC)
• Day temperature: 70-80ºF (21-27ºC)

USDA Hardiness Zone -First Frost Date- Last Frost Date

• Zone 1  -July 15th -June 15th
• Zone 2  -August 15th- May 15th
• Zone 3  -September 15th May 15th
• Zone 4  -September 15th May 15th
• Zone 5  -October 15th April 15th
• Zone 6  -October 15th April 15th
• Zone 7  -October 15th April 15th
• Zone 8  -November 15th March 15th
• Zone 9  -December 15th February 15th
• Zone 10 -December 15th January 31st (sometimes earlier)
• Zone 11 _No frost. No frost.

Terms and their meaning:

• EC=Electrical Conductivity

Plant injury resulting from excessive soluble salts may first occur as a mild chlorosis of the foliage, later progressing to a necrosis of leaf tips and margins. This type of injury is largely attributed to the mobility of soluble salts within the plant. As these salts are rapidly translocated throughout the plant, they accumulate at the leaf tips and margins. Once the salts reach a toxic level they cause the characteristic "burn" associated with excessive salts. For an accurate reading get an EC meter. Soluble salts in irrigation water are measured in terms of electrical conductivity (EC). The higher the salt content the greater the EC. In general EC values exceeding 2.0 are considered toxic to plant growth. Monitor your water quality frequently in order to avoid potential problems from soluble salts.

• FC=Foot Candles

Light intensity is a primary factor in the photosynthesis of all plants.  Full unobstructed sunlight has an intensity of about 10,000 fc. Where as an overcast day will produce an intensity of around 1,000 fc.  A window sill or light around a window or patio glass door can range from 100 to 5,000 depending of course what direction the light source is facing, or the time of year and your latitude.

• PPM=Parts Per Million

This unit of measure is relatively unique to the greenhouse industry and often there is some confusion on how ppm is calculated. I. To calculate the ppm contained in 1 ounce of material first solve for B: A x 75 = B A = the % active ingredient (AI) in the fertilizer B = ppm contained in 1 ounce of the material in 100 gallons of water Example: Calcium nitrate contains 15% N (0.15 x 75 = 11.25). If 1 ounce of calcium nitrate is dissolved in 100 gallons of water the solution will contain a II. To calculate the number of ounces of material required to make up a desired ppm concentration solve for C: C = Desired ppm conc. / B B = ppm contained in 1 ounce of the material in 100 gallons of water (from above). C = number of ounces of material to add to 100 gallons of water to achieve the desired concentration. Example: To make up a 250 ppm solution of calcium nitrate first multiply the AI x 75 (.15 x 75 = 11.25). Next divide the desired concentration by 11.25 (250/11.25 = 22). To make up a 250 ppm solution of calcium nitrate you would add 22 ounces to 100 gallons of water. Approximately 11.25 ppm N.