Practical seed starting

[willyb]

Practical seed starting

There are many ideas and strategies that work for growing seedlings. The following works for me to produce healthy plants and is cost effective.

Building a seed starting flat

• It can be any size that suits your available space to grow out seedlings.
• Space wasn’t an issue for me, except the area of the bottom heat source so I went with 16” x 24” for economy of materials. From a 48” x 48” sheet of ¼” plywood, I made 6 flats.
• Costs were: Plywood - $10. One 1”x3x 8’- $1.50. Some waterproof wood glue, staples, plastic and nails
• End cost about $2 each
• Yield 13 x 13 = 169 plants each
• Flats can be re-used for many years.
• Tools required. Minimum, a hand saw, hammer, stapler and tape Measure
• A power jig saw would save some arm ache, cost about $25

Build your flats

• Cut plywood to size
• Cut 2 sides and 2 ends of 1”x 3” frame to length. You don’t need to measure it, lay it on the plywood and mark it with a pencil.
• Glue and nail the frame together. Set it overtop of the plywood to keep it square or use a sheet of printer paper as a square.
• Glue and nail the plywood to the frame.
• Spread plastic over the completed flat, enough to cover the bottom and all sides. Staple it in and trim off excess. Leave enough to fold over the flat. Fold the plastic where required to keep it tight to the frame.

Soil

• When I use the word “soil”, I am speaking of a planting medium or strata, not “dirt”
• We north Americans are subject to marketing pressure to buy this brand or that brand. Many times I see the question asked, “What is the best soil to buy” The question we should be asking is “What do the plants need to establish a good root system and stay in good health until they are transplanted?”
• They need: A strata to grow in. Something to hold moisture. Air to the roots. A small amount of nutrient, preferably high in phosphorous. Light.
• We can make our own seeding mix that will do the job every bit as good as the “best” commercial ones.
• Buy the raw ingredients and mix your own.
• 2 parts peat moss, 1 part compost (Your own or local bagged .5 .5 .5) 1part perlite or vermiculite or a combination of both. A hand full of bone meal.
• Mycorrhizas - Don’t buy into this marketing hype for seed starting. Your plants will do fine with out it. Your own compost if in contact with garden soil or any healthy garden soil will contain Mycorrhizas, throw in a handful of your garden dirt if you want it.
• Micro-nutrients. The compost will have all the plant needs to get to transplanting stage.

Adding soil to the flat

• Add soil to the top of the frame. Level and water until evenly moist. Compact gently with a block of wood. Do not over compact as you want space for air in the soil.

Plant seeds

• Place seeds on the surface. Press into soil with pencil, your finger or the handle end of a screwdriver.
• Dust with a thin layer of peat moss 1/8th inch or less, level and compacted lightly with your hand or block of wood. Do not water the peat moss. It will act as a moisture retainer. (mulch) and prevent damping off.
• Fold the plastic over the flat to help retain moisture. Not tight, allow for air movement to prevent mold and damping off.

Germination

• Add bottom heat. Not necessary, but will advance germination by a few days. Keep ambient temperature over 60 degrees and not over 90 degrees for tomatoes and peppers until seeds have germinated, afterwards less than 70 degrees for growth.
• Your shop light, turned upside down will work as well as a heat mat.
• When the first seeds germinate, remove plastic.

Light

• When the first seeds germinate, put them under florescent lights. A 2 bulb T8 shop light is the most cost effective, under $20. GE plant and aquarium bulbs will provide the best growth and are cheap. GE kitchen and bath are also good.
• T5 bulbs are not cost effective. The bulbs and fixtures cost so much that for the energy savings you will not recover the cost in 10 years.
• I keep the lights on 24 hours a day so as not to have to worry about timing or a timer. 16 hours should be a minimum to keep the plants compact.
• Keep the light no more than 1” above the plants.
• A south facing window will work, the plants will be “leggier”

Water

• Do not over water. The initial water should be enough for all seeds to germinate.
• If kept on the dry side the roots will grow long seeking water.
• Water only if the soil feels very dry. Take a sample from the bottom soil with a straw to test.
• I use a 4 -10-4 fertilizer at 1/5th the recommended strength in the water after the first true leaves form to promote root growth. At this concentration you will not burn the plants. More is not better.
• If you are an organic grower, use dilute molasses tea or similar. High phosphorous, low nitrogen.