How To Start Your Garden Seeds Indoors
This is the second year that I’m starting my garden seeds indoors! I wanted to share some tips and tricks for others who want to start seeds indoors too.
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Light & Warmth
Light and warmth seem to be the two big keys to starting plants indoors. It’s tempting to start seeds on a windowsill, but I found that 1) the sunlight wasn’t bright enough through a window (though I don’t have any south-facing windows, only east or west facing windows) and 2) the windows are cold in March and April. So for me, a plant grow light in a warm location is a must.
Small tomato, pepper, and zucchini plants under the AeroGarden 45W LED Grow Light Panel
I tried several plant grow lights:
The AeroGarden 45W LED Grow Light Panel is easily my favorite. It fits perfectly over standard-sized starter trays. It’s super bright and produces some warmth too. It comes with an adjustable-height stand and can also be hung.
One negative: This light doesn’t have a built-in timer. I bought a super simple outlet timer to automatically turn on the light for about 10 hours a day.
Runner up: the AeroGarden Trio Grow Light was the first light I used. It was effective but a bit too small so I upgraded. Bonus though: this light has a built-in timer.
Another option: this Gooseneck LED Grow Light. As my plants grew bigger, I needed another grow light. This was perfect and it also has a built-in timer.
For warmth, I put my plants on a table directly below a heat vent. This served as a perfect heat source, though it did dry out the soil faster.
If you don’t have a heat vent in a convenient location, there are a variety of heated mats available to put under the plants. I didn’t test any of them myself though!
Soil, Pots, Trays
Burpee Coconut Coir - This is my favorite seed starting mix. Put it in a 5 gallon bucket with water and it expands quickly.
Why a “seed starting mix”? Seed starting mixes are free of pathogens that might harm tiny plants. They’re also low in nutrients since seeds have enough energy stored to begin growing. The first leaves on a plant are cotyledons or “seed leaves” and it’s not until the next set of leaves - “true leaves” - that the plants need nutrients in the soil. See the “nutrients” section below!
Burpee Seed Starting Tray - The first home for the plants! The small cells are perfect for starting lots of seeds.
Burpee Potting Soil - Once the plants are a little sturdier, I transfer them to a larger pot with potting soil. I tried several types and this was my favorite - it drains nicely and was easy to work with!
Nursery Pots (5in, 4in, 3.5in) - I transfer plants into these when they outgrow the seed starting tray.
Plant Trays - I use these 20x10in trays to hold the nursery pots.
Plant Tags - To label each plant.
Repotting Mat - This keeps the mess contained (mostly) when I’m filling pots with soil!
Seed starting tray on the left, nursery pots on the right, all under the AeroGarden Trio Grow Light
Plants in nursery pots with plant tags
Nutrients
Miracle-Gro AeroGarden Liquid Plant Fertilizer - I had this on hand from my AeroGardens and since it’s designed to be used in AeroGardens, it has all the nutrients that growing plants need. I mixed it 2ml to 1 gallon of water and used it once a week to water the plants. If they needed water more often, I just used plain water.
Note: I begin using fertilizer once the plants start to grow a second set of leaves. They have enough energy stored to grow on their own until then.
3ml Pipettes - These made it super easy to measure the fertilizer and add it to 1 gallon of water!
Hardening Off
There is one more thing to know about: hardening off the plants! The great outdoors is rough with bright sunshine and strong wind. The hardening off process strengthens the plants to make their transition outside go smoothly.
About two weeks before moving the plants to an outside garden, start the hardening off process:
On a nice day, put them in a shady spot outside for an hour
The next nice day, increase it to two hours
Keep increasing the length of time until they can spend the whole day outside
Introduce direct sunlight starting with just a few minutes and increase it slowly - last year my plants were sunburnt from too much direct sunlight too quickly!