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How to Grow A Tomato Plant Indoors with LED Bulbs We set out on an experiment with the objective: grow tomatoes indoors as simply as possible. Without investing in massive lights, equipment, and countless tools, we decided to stick to the basics to see if we could bring a dwarf variety tomato plant seed (Vilma) to a mature plant with ripe fruits. And we did just that. In 88 days. While constantly documenting and putting together the photos into a three and a half minute time-lapse. Background & Equipment We know that tomato plants are classified as “high-light” plants and that they thrive with high PPFD (light intensity). We see these plants do very well when they receive PPFD levels up to around 600 µmol/m2/s. We also know that the bigger pot size a plant gets, the more space it has to grow massive root systems.  But what happens if we only have a basic setup with a small light source and a tiny (4 dl/13 oz) pot? Can we still bring the plant to maturity,  and will it carry fruits? This was our challenge. Here’s the equipment that we used and links, if you want to try on your own:1x Seed We bought ours from a Swedish shop but similar seems can be found here:Amazon: https://www.amazon.com/s?k=vilma+tomato+seedsOr https://www.renaissancefarms.org/product/vilma-micro-dwarf-tomato/ 1x Container, eg food or fruit (4 dl/13 Oz) Medium: ~35g/1 Oz (packed) Coco coir. Soil works, too.Small pack: https://www.amazon.com/dp/B01MRGXSAA/Big pack, premium: https://www.amazon.com/dp/B00518ECYG Lamp: 5.7W 2700k 345lm LED E27 Bulb with 36 degree focusing lensesWe used this lamp: https://www.amazon.co.uk/dp/B00MB5Y12UBut for America based growers, the following lamp seems on paper to be a fair alternative, although we haven’t used it ourselves:https://www.amazon.com/dp/B071LNFTYMLamp holder: IKEA Tertial lamphttps://www.ikea.com/us/en/p/tertial-work-lamp-with-led-bulb-dark-gray-00424985/ But any lamp holder that matches the bulb’s E27/E26 base would work.  Hydroponic or general nutrientsEasy to use pre-mixed for beginners: https://www.amazon.com/dp/B000RNCKQ2Mix & match yourself for experienced growers: https://www.amazon.com/dp/B017H73708Yara nutrient mix for advanced and large scale growers.https://www.yara.co.uk/crop-nutrition/fertiliser/soluble/yaratera-kristalon-scarlet/https://www.yara.co.uk/crop-nutrition/fertiliser/soluble/yaratera-calcinit/   From our previous PPFD tests with household bulbs, we knew that this 5.7W LED bulb performs well and can produce a high PPFD at a distance of between 10-14”/25-35cm. However, these bulbs have a rather small light footprint, which means they don’t cover a large area. Would it still be enough? A 2700K spectrum is rarely used for a full grow cycle, if at all. There’s an old misconception that plants want 6500K as they have developed in sunlight. Plants will grow in almost any light, just with different shapes and results. Even with 2700K. We chose this Kelvin for simplicity, as the majority of all off-the-shelves household bulbs are produced with this color spectrum. It is also a nice hue to have lit in the open space for 24 hours each day. As we wanted to record the entire grow, we realized a few days in that we’ll need to give the plant light 24 hours of the day, every day, to get decent photos. The plant would likely have preferred at least a couple of hours of darkness where it could rest and muster strength, but for our convenience, we pushed it 24/7 with light. So, with seemingly poor starting conditions, can we still make it work? Is the tomato plant strong enough to thrive even when it’s given far from ideal circumstances to grow? Grow Process The tomato seed was germinated on top of wet paper towels enclosed in a box for two days then transplanted 5mm deep into a dampened coco medium inside a 4 dl/13 Oz container. The plant grew healthy and really started to look like a plant after four weeks.The plant was watered with the same mix of nutrients and concentration throughout the whole grow.The NPK was 2-1-3, the EC was 1.3 mS/cm, and the PH was 6.0.Measuring the nutrient solution this carefully is not necessary to succeed and especially not if growing in soil. We share these numbers to be precise but plants will grow fine with less strict nutrient planning. The tomato plant was watered every time the medium started to look dry on the top or when the plant started drooping from dehydration. The pot had drilled holes in the bottom and was watered heavily every other watering to prevent salt build-ups and to wet the medium thoroughly. Another 10mm of nutrient solution was also added to the outer container as a small reservoir, to be able to water less frequently.It was initially given a PPFD intensity of 150 µmol/m2/s (around 45 cm/18