So I've made several mistakes while growing my tomato plants, and I'm still very new so bear with me. I'm concerned about the spots that keep forming on the leaves of the plants (only showing one plant). The spots seem to start at the bottom leaves and don't really form at the top leaves, although there is slight discoloration. After a day or so they also dry up and look almost burned or bleached. At first I thought that it was a deficiency? But it might also be overwatering? I've been misting the leaves which I just now learned isn't good. They are a potted variety that are only my balcony as long as it isn't too cold (which varies due to the weather in Sweden).

Another concern I have is the white spots in the soil, as shown here:




They weren't present as seedlings and look like small lumps of soil that have turned white. When touched they break into a washing powder consistency. Is it some sort of mold (overwatering?)

I see two or three issues, related.
Is it potted in pure coco coir? Are you fertilizing? What is that container — size? Drains holes?

Looks to me like lack of nutrients. Get it into regular potting soil, feed it a liquid fertilizer, either for bloom & fruit or specifically for tomatoes. And tell us about that pot.

Yes, do not mist. Keep the soil uniformly moist at all times, not soggy. And it should be getting as much sun as possible.

NMoasis said: I see two or three issues, related.
Is it potted in pure coco coir? Are you fertilizing? What is that container — size? Drains holes?

Looks to me like lack of nutrients. Get it into regular potting soil, feed it a liquid fertilizer, either for bloom & fruit or specifically for tomatoes. And tell us about that pot.

Yes, do not mist. Keep the soil uniformly moist at all times, not soggy. And it should be getting as much sun as possible.

What is coco coir? Im using normal potting soil as far I know. The container is made of plastic and is just something reused from the grocery store. It's about 12 cm in diameter. It has 8 tiny holes about 1/2 cm. I can add more holes, but they wouldn't be any bigger than the premade holes. Do I need more drainage?

I've noticed that a few smaller plants have a purple tint to the underside of their leaves. I've heard that it might be a nitrogen deficiency? Is there any fertilizer that is bad for tomatoes? I have two different fertilizers but neither are specifically for tomatoes. I don't want to kill the plant by feeding them something they can't handle.

In terms of watering, should I be using a watering can, or use a tray?

You don't need fertilizer specifically labeled for tomatoes. You just need a general balanced product and use it according to instructions. Tomatoes need a steady supply of nutrients. Tell me what the two products are that you have and what is in them.

Water the soil from the top, do not water the leaves. Saturate all of the soil. Do not allow the soil to dry out between waterings. Very soon you will need a larger container. What type of tomato it that... determinate? Indeterminate? Dwarf? That determines what size pot you need. Generally, unless it's a dwarf, the smallest recommended container size for a tomato plant is 19 liters (5 gallons).

Finally, tomatoes need to be in full sun for at least 8 hours a day.

NMoasis said: You don't need fertilizer specifically labeled for tomatoes. You just need a general balanced product and use it according to instructions. Tomatoes need a steady supply of nutrients. Tell me what the two products are that you have and what is in them.

Water the soil from the top, do not water the leaves. Saturate all of the soil. Do not allow the soil to dry out between waterings. Very soon you will need a larger container. What type of tomato it that... determinate? Indeterminate? Dwarf? That determines what size pot you need. Generally, unless it's a dwarf, the smallest recommended container size for a tomato plant is 19 liters (5 gallons).

Finally, tomatoes need to be in full sun for at least 8 hours a day.

Yeah the full sun is an issue since it's been getting colder lately.. I'm not sure what the types mean, but they're supposed to be a container/pot type I think? I gave the ingredients for one of them and I'll post the other ASAP. It's in Swedish so I'll try to translate it as well as I can.

It contains: 5% nitrogen (3% pure nitrogen / 2% ammonium nitrate), 1,7% water-soluble phosphor, 5% potassium, 0,010% water-soluble boron, 0,009% water-soluble copper, 0,0034% water-soluble iron, 0,0018% water-soluble manganese, 0,001% water-soluble molybdenum, 0,0018% water-soluble zink.

If it's labeled as a "patio" plant, you can possibly grow it in about a 2-3 gal container. Knowing what type of tomato it is would be helpful.

Interested in knowing ingredients and percentages of the other product.

Yes, sun is an issue.

NMoasis said: If it's labeled as a "patio" plant, you can possibly grow it in about a 2-3 gal container. Knowing what type of tomato it is would be helpful.

Interested in knowing ingredients and percentages of the other product.

Yes, sun is an issue.

Not sure if we call them "patio" plants here, but it says that it's a "pot type" that can be grown directly, but because of it's compact size and short growth height, does well in containers. It says 'balkonzauber', so I guess that's the cultivar?

The other one contains, 3,5% nitrogen, 3% water-soluble phosphor and 3% water-soluble potassium.

Do you have any experience with indoors lighting for tomatoes?

Ha! As it turns out, our very own @Dave, who owns Victory Seeds,, might be the best person to advise you. "Balkonzauber" translates to Balcony Magic" and his company carried the seeds. Review here:

https://victorygardeners.com/p...

I'd use that second fertilizer, but see what Dave says .

I don't use lights. Others can perhaps assist.

Your tomato needs: potting MIX (anything that says "soil" is NOT good for pot/container growing), a bigger pot with bigger drainage holes and more fertilizer - one SPECIFICALLY formulated for tomatoes!

I have grown almost all my tomatoes in various size containers for many years, from a re-purposed waste paper basket to 94.6 liter fabric gro bag. I researched your plant: it is characterized as a micro dwarf, 40 cm tall, producing 2-3 ounce cherry tomatoes that ripen all at the same time.

Potting MIX contains perlite, a non-nutrient extruded rock substance that prevents compaction and improves drainage of the growth media. Potting soil doesn't, leading to compaction, poor drainage and a suffering (if not dead) plant.

I strongly advise a tomato fertilizer, since a tomato has specific macro- and micronutrient needs. I don't know if you use both fertilizers together, but even if so they're starving your plants (which will result in anywhere from a dead plant to poor or no production.

I'm in America and am unfamiliar with what types of fertilizers etc are available to you. Just the macronutrients alone (the NPK = nitrogen-phosphorous-potassium) will not fully support growth. A formulation of 5-10-10 or even 7-7-7 is insufficient UNLESS it also has the micronutrients calcium (Ca for plant growth and prevent blossom end rot - BER- where the bottoms of tomatoes rot), sulfur (S for growth, create proteins and WITHSTAND THE COLD) and magnesium (Mg as the center of the chlorophyll molecule where the plant turns sunlight into energy for itself). Only Ca and Mg can be supplemented.

Some other important micronutrients are:
Zinc (Zn for plant growth)
Boron (B for flowers, pollen viability and fruit ripening)
Last, but not least:
iron (Fe)
copper (Cu)
manganese (Mn)
molybdenum (Mb)

Of course, when tomatoes are grown directly in the ground, the trace amounts needed are almost always available. But when growing in a pot/container. . . it is up to the grower to supply the necessary micronutrients. So mix the fertilizer/supplements into the potting mix BEFORE introducing the plant!

Although you have a micro dwarf, its roots are nearly full size: the size of the new pot needs to be double: at least 24 cm. Only one central drainage hole is required, also doubled in size to 1 cm. Cover the drainage hole (inside the pot) with window screen mesh - to prevent the potting mix from draining out!

Some put their tomatoes outside during the day when its 15.6 Celsius (C) and outside at night when its 10 C. At 4.4 C at night, the plant's growth is stunted and it has wilted leaves. I think I can also see evidence of frostbite on the crispy edges of some leaves.

Those white spots on your soil that turn to powder when touched is indeed either mold or fungus. To prevent, sprinkle the surface with cinnamon (from the kitchen. . . sorry, Mom!) and bottom water using a tray. The plant will use that drainage hole to take up however much it needs. . . in about 26-30 minutes.

Lastly, come on over to the 2023 Tomato Gardening thread, in the Vegetables and Fruit forum. There's alot of us friendly tomato heads, willing to help/advice/support all levels of tomato growers!

Welcome to the fascinating world of gardening!