Spring is right around the corner, and it is time to get those seeds growing! Because I live in Minnesota and am a renter, I do not have a greenhouse yet, and the weather in Minnesota is too unpredictable to even think about starting seeds outside in a cold frame. At this time of year, I have to grow indoors, and over the past few years, I have developed 8 Steps to Starting Plants Indoors.
When should you start your seedlings? The answer to that question is: it depends! It depends where you live and what you are planting. Where you live matters because it will determine the last frost date, which is the last date that you could potentially have plant-killing frost (based on probabilities). To find your last frost date, go to these links if you live in Canada or in the USA.
Our last frost day is typically May 10 in the Twin Cities. That is a key date since planting outside before that date is tempting the unforgiving fates. Don’t believe me? I have seen snow in late May, and one year the ice did not come off the lakes until almost June! Welcome to the frozen tundra.
What you are planting matters as well. Seed packets and catalogs will have information about when and how to sow particular seeds. Expert growers have tested the seeds and compiled this information, so it makes sense to follow their recommendations. Sometimes starting plants indoors really early does not result in super producing plants!
8 Steps for Starting Plants Indoors
To start your plants indoors, you will need to gather materials including soil, containers and seeds. I will have a post discussing those elements this week.
Once you have gathered your materials, you are ready to plant seeds and get going! Here are the 8 steps for stating plants indoors that I use:
- Use seed trays, refillable cells or containers, heating pads, lights and timers. You can get up and running for less than $100, and I will have a post discussing how to set up your growing area.
- Add your soil mix to the cells or containers. Do not fill the containers to the top yet! You will be adding seed to the cells or containers and covering the seed with soil.
- Add seeds to the cells or containers.
- Cover the seeds up with a layer of soil.
- Add some water to the bottom of the seed tray. You want the soil to be damp but not soaking wet
- Put the seed trays onto the heating pads. Plug the heating pads into a surge protector. Note that you will not be plugging the heating pads into the timers. You want the soil to be warm and encourage plant growth.
- Put the grow lights close to the top of the tray (about 1” to 2” away from the top of the trays).
- Check your trays once a day and water as necessary.
Words of Caution
Over the years, I have had my share of problems, particularly with peppers and tomatoes. Most of the problems I have had are related to heat and water.
I have an unfinished, uninsulated basement. It can get pretty cold down there, and plants like peppers want the soil to be around 70 degrees Fahrenheit before they sprout (optimal range is 70 to 95 degrees Fahrenheit). They can be pretty finicky in a cold Minnesota basement!
When using seed trays with heating pads, check the moisture of the soil once a day. The pads will heat the soil, and moisture will evaporate over time. You will need to check the soil once per day to make sure it is optimal for growth (slightly damp, not soaking wet). Too much water will create other problems.
Soil naturally has bacteria and mold in it. Under the right conditions, you can activate those molds and damage or kill your plants. The biggest culprit is damping off disease, and it can kill whole seed trays full of precious seedlings. According to the University of Minnesota Extension Service:
[The] Disease is particularly severe in garden seedlings when seeds are planted in soils that are too cool for optimal germination or when weather turns cool and wet after planting resulting in slow germination and growth.
The damping off pathogens thrive in cool wet conditions. In addition, any condition that slows plant growth will increase damping off. Low light, overwatering, high salts from over fertilizing and cool soil temperatures are all associated with increased damping off.
I will create a separate article about damping off disease based on my experiences last year, but the keys to successful seedling growth is keeping them warm with heat pads and being careful when watering. Here are some good tips:
- Check your trays once per day. Make sure your soil is damp (not doggy or too wet). The heating pads will cause evaporation, so make sure your seedlings have enough water. Too little water and your seedlings will die.
- Don’t water your plants from the top down. Water the trays, not the actual cells or container. Let the water wick up into the containers. Adding water right to the soil encourages molds to grow, especially in a basement environment.
- Do not use plastic hoods over your plants! You’ll notice condensation on the plastic hood, and that water might drip onto the soil and cause molds to activate. At the same time, the soil might be drying out, and your seedlings might dehydrate and die. Ditch the hoods; they aren’t helping you.
I hope you give these 8 Steps for Starting Plants Indoors a try. I have had successes using these steps by failing a time or two. By using these steps, you should start growing some seedlings for your garden in a 7 to 10 days! Let me know your experiences growing seedlings. What did and didn’t work for you?