Seedlings newly up-potted into 4 inch pots on November 27, 2024.

With the advent of micro tomatoes, I decided to see if I could successfully grow some under lights in my basement. I set up two high output LED light strips from Gardener’s Supply My great DIY husband made supports from PVC pipe and I got Vivosun adjustable hangers. I selected two tomatoes: micro Tiny Tim and “compact” Patio Choice Yellow for my first attempt. Seeds were sown in Fertilome Seed Starting Mix (peat based) on November 9 and they were placed under the lights on a seed heat mat. Germination was good and I up-potted into 4 inch pots on November 27. Also sprayed the plants with an organic spray to prevent pests.

The Grow Light Setup.

Yes the tomatoes are sharing space with my wintering tender agave collection and germinating cat grass. Notice they are also getting some supplemental natural light from the window in the background. Heat mats are plugged in since the basement cools off into the 60’s at night.

Fruit on January 10, 2025 – Patio Choice Yellow (l) and Tiny Tim (r)

The plants grew well and I moved them to gallon pots over Decmber 24-27, resprayed for pests and raised the lights. The plants started blooming almost immediately and as of January 10, there is small fruit on both Tiny Tim and Patio Choice Yellow.

I am feeding weekly with Age Old Fish and Seaweed fertilizer. I put out a sticky trap to monitor for insects and have seen only fungus gnats. There is some leaf yellowing off and on. Not sure if it is disease or just lower leaves not getting enough light. When I see yellowing foliage I remove it.

Today, February 12 , I picked two almost ripe Patio Choice Yellow tomatoes. There is excellent fruit set on both tomato varieties. One mistake I made is choosing varieties with different heights. I’ve adjusted the grow lights at an angle to keep them around 4″ above the top of the plants. I’ve also topped the Patio Choice Yellows. There is very minimal leaf yellowing at this point as well.

The timeline:

• Seed sown November 9
• Moved to 4 inch pots November 27
• Moved to gallon pots December 24-27
• First fruit picked February 12.

So 74 days from sowing to first ripe fruit.

Fruit in various stages on February 19, 2025. Note the diseased foliage on the Patio Choice Yellow in the back. This variety had a lot of yellowing/brown leaves – that one plant was so diseased I removed it on February 24. Tiny Tim’s foliage has remained healthy except for some lower leaves which I think were not getting light. The yellowing on the Tiny Tim far left I think is scalding from being too close to the lights. I have since raised them around 2 inches.

Some of the fruits collected over a few days. I tasted one of each when ripe – one half without salt and one with (thank you Lena Halberstadt for that tasting tip). Patio choice yellow was sweeter but still had nice acidity. Tiny Tim was more tart but still had good tomato flavor. The flavor of both tomatoes improved with a little salt, bringing out the sweetness. I was more impressed with these two tomatoes than previous micros I have grown outdoors. Lots of work is being done on micro tomatoes and I look forward to more flavor improvements.

My take aways from my first attempt at growing tomatoes under lights:

• The two LED light strips from Gardener’s Supply provided enough light to grow and produce fruit when on 16 hours/off 8 hours.
• Heat mats helped keep the temperature up in my cool basement so they stayed on.
• Spraying twice with organic pest spray – I used Grower’s Ally Plant Defender 3.
• I think using fresh potting soil helped prevent leaf disease.
• Fertilization with Fish and Seaweed fertilizer proved adequate – maybe add Espoma tomato tone when seedlings to into gallons.
• If you are growing more than one variety – choose plants with similar heights.
• I will sterilize the gallon pots next time to see if that prevents the leaf disease.

I want to compare flavor when grown outside to under lights so am going to start some of both varieties later this spring. Next up will be a second round of Tiny Tim. Just two plants so I can devote time to outdoor gardening in a month or so.