Jan Trent (MG08) on Starting Seeds

Starting Plants from Seed                           

Since 2008, the CVG flower team (known now as Plants4Habitat team) has started over 1000 seedlings.  The first year, Joan Hermann, Julie Ligon and I had no idea what we were doing…the seeds germinated anyway!  After 3 years, several Dixon Garden Seminars and troubleshooting internet searches here are a few things we have learned.

Preparation, preparation, preparation:

v  Seed trays and flats

Ø  The job is easier if you purchase professional seed trays – 15, 38, 40, 50 cells per tray and flat trays (no holes).

§  Pros:

·         Seed trays usually come or can be purchased with their own flat (no holes) trays, making them easy to handle. The flat trays allow you to water from the bottom and they work great during the hardening transition period from indoor to outdoor.

·         Trays can be used over and over.

·         Inexpensive – under $3 per set (seed and flat tray)

§  Cons: Must be washed with bleach and soap solution after use.

Ø  Jiffy Peat Pellets and trays – 18 to 72 pellets in a tray

§  Pros:

·         Quick, no mess and easy plant for beginners.

§  Cons:

·         As the plants get larger they get top heavy and fall over

·         Small amount of dirt, root bound quickly

·         Dry out easily

Ø  Sowing Trays – Roasted Chicken containers with clear tops are great.  Punch a few holes in the base with a sharp knife (punch the holes from inside the base allows water to drain).

§  Pros:

·         Recycling

·         Great for smaller seed

§  Cons:

·         Damping off (mildew growth)

¨       First sign of germination – take the top off, place it loosely back on at night

·         Transplanting seedlings to seedling trays is time consuming

v  Wash trays, seedling trays and pots after use with bleach soap solution.  Dry and store.

Ø  Use 1 to 2 tablespoons of bleach and liquid dish soap to a gallon of water.

Ø  Bottle brush and mop work well on seed tray cells

Ø  Soak trays a few minutes makes the job easier

Plan, plan, plan

v  Best not to take vacation during this 6 to 8 week germination/growth period if you are the seedling caretaker.  Moving mass of trays to someone else’s house is not easy. If you have someone tending to the seedlings while you are gone it should be 2 to 3 times daily, especially if they have been transferred to outside.

v  Who is going to transplant the seedlings to their final destination?

Ø  Jiffy peat pellets and trays for inexperienced volunteers and educational outings.

§  Pros: Easy for small children and large groups to handle.  Suggest marigolds, sunflowers, zinnias, etc - medium and large size seeds.

§  Cons: These dry out rather quickly and the pellets are small.

Ø  Seed and flat trays for more experience (seasoned volunteers)  

§  Pros:  Plenty of room for the seedlings to grow.  Use these for your expensive, hard to start seeds.

§  Cons: Hard to remove the seedlings from the tray (we found plastic forks used as little shovels work best)

Ø  Sowing trays for the more experience (seasoned volunteers)

§  Pros: Best way to start minuscule and small seeds.

§  Cons: Time consuming and requires manually transplanting small seedling to seed trays.  With some guidance and patience a young adult can transplant these small seedlings.

When to plant your seeds - two different approaches:

v  Count backwards to get your start dates for your seeds:

Ø  When do you want to transplant the seedling to their final destination?

§  Plan 4 to 6 weeks for growing a seed from germination to transplant ready

§  Germination can take 1 to 2 days up to 21 days!

§  Add the two - the growing period and germination days together and count backwards from your transplant date.

§  Example: Most flowers are transplanted after April 15 - seeds would be started between Feb 8 and March 11, 2011 depending upon their germination period.

§  Still some seedlings might lag behind and need transplanting later than planned.

§  Other seedlings might grow too fast if the conditions are right. Slow down on the fertilizer and make sure they get plenty of water to survive.  If they become too root bound, transplant to a larger container.

v  Start all seeds at the same time

Ø  Plant all seeds germinating at similar times in the same seed tray

§  You have seedlings needing the same fertilizer and water in the same seed tray

§  Prevents mildew from happening

§  Prevents shading newly germinated seedlings

Ø  Plant the seedlings after April 15 and/or as they mature

§  Transplanting at different times to their final destination could create problems.

·         Disturbing roots of the other transplants you planted a week or two earlier

·         Disrupts the overall landscape design or you can’t get the plants where they need to go.

Label, label, label

v  You will not remember!!  Label consistently; pencil is okay as long as everyone can read it.

Ø  Name of seed, height, space

§  You only have to look at the seed packet once

§  The seed packet was accidently thrown away

Ø  Have them ready before you start your seeds

Soil

v  Use seed starting soil – very fine humus

Ø  Some articles suggest sterilizing the soil either by baking or microwaving, but we have not done this.

Ø  Usually comes dry, moisten with warm filtered water – 4 hours before used

§  Soil feels lightly damp

Ø  Lightly pack seed and sowing trays to 1 inch from top.

Fertilizing:

v  After the seed trays and flats are placed in your greenhouse – water from the bottom with MegaGro Concentrate - a natural growth stimulant.

v  Once germinated – MegaGro and fish emulsion (¼ to ½ regular dosage on fish emulsion) every time you water for 4 weeks

v  After 4 weeks, fertilize with MegaGro and fish emulsion full strength twice a week.

Making your greenhouse:

v  Folding card or rectangle table

v  2 - four foot florescent lights with plug-in (Home Depot, Lowes)

Ø  Set up the folding table

Ø  Hang the florescent lights under the folding table

§  Make sure you can adjust the height of the lights as the seedlings grow – string or twine works well.

§  Set the lights on a timer – lights on 5-6 am to 8-9 pm

Ø  Allow the lights to be 2 to 3 inches above seedling trays

Ø  Raise the lights as the seedlings grow

v  You may place a regular heating pad under the seedling tray – turn on low for about 15 to 30 minutes per tray to warm the soil

Ø  Pro: Warmth needed for the seedling to germinate

Ø  Con: Can promote damping off (mildew growth)

v  You can cover table with clear plastic sheeting

Ø  Pro: Warmth and contains humidity

Ø  Con: Can promotes damping off

v  We’ve done both but only the first couple of days.  You have to be very careful not to overdo – damping off will kill seedlings.

Ø  Remedies for damping off:

§  Sprinkle cinnamon lightly on the seedling and seed cell

§  One tablespoon of Hydrogen Peroxide to 32 ounces of water in a spray bottle – spray lightly on seedling and seed cell

§  Run a fan at low speed to help dry out the soil

Hardening the seedlings:

v  Keep them on a table or bench if possible.

Ø  Prevents cats, dogs and/or other animals from walking on them

Ø  Helps keep bugs at bay

§  If needed use lightly - Sevin and/or slug control – more of a problem for July, August seedlings

Ø  If you live in an area with roaming animals set up a cage to protect your seedlings.

v  Filtered sunlight

Ø  A patio table umbrella with material that is coarser, thicker than screen door material works perfect!

Ø  An old table umbrella or an old sheet to make a shaded area – holes may be place in either to give a more filtered sun effect.

Ø  Move the trays around as the plants lean towards the sun.

v  Rain/Water

Ø  Do not allow your seedlings to set out in the rain

§  Tennessee thunderstorms can be damaging – it can ruin a whole seedling tray

§  A couple of days of rain can overwater the seedlings and start the damping off (see above)

Ø  Check your seedlings every couple of hours when outside, they dry out very quickly

It’s Seed Party time!!!

Invite a few of your garden buddies over for some fun!  Have one person read the directions on the seed packet for the depth to plant seed; this person should also know what seed goes into what tray for germination purposes.  Two people tend to one seed tray – one to adjust the depth for the seed in the soil, another to plant (two seeds in each cell about an inch apart if possible), label, and cover with soil.  Start a new seed.  This prevents double seeding, backaches and confusion.

Once all the seeds are planted, place in greenhouse.  Pour the MegaGro/water solution in the bottom of flat trays, NOT on top of the soil.  Let set for 15/30 minutes and drain excess water.  Do not keep MegaGro/water solution; the solution will only be good for an hour or so.  Keep soil moist not wet.  If you feel the top of soil is drying out too fast make up the Hydrogen Peroxide solution (see damping off under “Making your greenhouse”).  Check moisture several times a day until germination.  Once germinated, if you have used plastic sheeting over your greenhouse REMOVE IT NOW.  Maintain the lights just above the plants and move the seed and flat trays around to prevent the plants from getting leggy (when a plants central stalk becomes spindly and unstable).  This might have to be done twice a day.

As soon as the days are above 55 - 65 degrees and sunny, set the plants outside in filtered sun.  Start with a couple of hours the first day and add 2 to 3 hours each day.  The rest of the day they should sit in shade.  The plants should be brought into the house or an enclosed garage at night if temperatures are below 35 degrees.

If seedlings outgrow their cells, transplant to larger containers until they can be placed in their final destination.  The last week before transplanting to their final destination harden off the plants to full sun, just like you did to the filtered sun.  When you are ready to transplant, allow the plants to be a little dry (as if they are ready or need to be watered).  Dig the hole at final destination, soak the hole with water/fertilizer solution, transplant the plant to the hole and water again.

--Janet Trent, MAMG 2008

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