Getting the Most out of Your Seed aka Water Management in Plugs Will Healy Senior Technical & Research Manager
How do we know what works?
Seed Storage Cool (2-9C) DRY <20% RH Refrigerator 40+% Sealed package <25% Warm+50% RH Cooler = 90+% RH
Soil Matters Water holding capacity ph Blond, tan or black peat No hydrated lime Nutrient charge P+micros
Checker board drying is not going to uniformly germinate Keep soil in flat filler moist!
Uniform Wetting of the Soil
Filling to the bottom Taper controls bridging Right moisture squeeze no stick Uniform soil drop across tray and not ridge down tray Paddle rubbers need regular replacement
Dibble to center the seed
Getting one seed in the cell Bigger the seed (pellet) the more accurate the placement Higher vacuum = better singulation Variable vacuum pressure = failure Use a vacuum by-pass regulator to maintain constant vacuum without bleeding
To Cover or Not to Cover is the question! The amount of covering material in the hopper dictates the uniformity of covering Automated loader to maintain constant depth in hopper
1. Hydration 2. Cell Proliferation 3. Root Initiation Shoot Elongation Root Growth
Germination is the process that begins with the absorption of water and ends with the elongation of the root
Physiological Process 1. Seed Coat absorbs water 2. Water moves into the inner membrane 3. Starch breakdown machinery activated Dry 4. Cells multiply and elongation Process begins 5. Seed coat cracks 6. Radicle emerges from seed 7. Seed has germinated Koning, Ross E. "Seeds and Seed Germination". Plant Physiology Website. 1994. http://koning.easternct.edu/plants_human/seedgerm.html
Training Issue Growers with nothing to do Water! A Grower s Job is to Dry out Trays to Grow Roots Pencil Watering -> Plan What to Do Next Day
Commitment to Germinate starts at the water tunnel Water before and after overcoater Enough Nozzles to provide correct amount Post water tunnel booms Low pressure to avoid flooding
Water Tunnel Uniformly add water to start germination process Pressure & gpm per nozzle Number of nozzles N1 = glue seed N2 = moisture around seed N3+ = moisture in soil
What s enough water? 512-288 Raw 900-1000 gm Pelleted 1000-1200 gm
What about Pellets? Enough water to soften pellet Keep moist prevent drying out of shell By day 3 bowl of oatmeal or cracks Bowl of oatmeal with a raisin on top
Precision Moisture Targets X Excess water (weight) prevents dry down and promotes hypocotyl stretch
What happens when there is too much water? Crust
Watering vs Flooding Day 0-5 key period Irrigation speed Grit is critical
Optimizing the Germ Chamber Fog, No Water LEDs to promote rapid germination
Why light? Pentas need light! Edge of the Cart towards lights Bottom shelf of cart Excess water buried the seed
Stage 1 Moisture Sowing to radicle emergence Maintain critical moisture level Starting point Tunnel -> 48 hours Day 3 5 Change point? 40-60% germ Rate of change
Non-Uniform Begonia Note the dry down below the target dry levels (white line) of the early stages of development which caused root damage and stunted plants early in production.
Stage 1.5 Moisture 40-99% germ Finishing off germination Balance germ vs hypocotyl stretch Wetter = germ + hypocotyl stretch Too Dry = germ + short hypocotyl
WbW Stage 1 & 2 Note the gradual dry down (red line) after germination is completed Germination Cotyledon Unfolding
Watering Technique Vol*speed = Qty/cell 3 5-3 5 3-5
1. Hydration 2. Cell Proliferation 3. Root Initiation Shoot Elongation Root Growth
As Freud said and sometimes it is just the seed.
A final comment If it is not measured, recorded & ANALYZED it didn t happen. Questions?