📌 Quick Summary: Troubleshooting Stalled Eggplants
- 🍆 The Root of the Problem: If your eggplant or pepper seedlings stall and stop growing, it is almost always an issue below the soil line (poor root development).
- 🪴 Potting Up: Don’t leave seedlings in tiny 6-cell plug trays for too long. They need to be moved into 16 oz (0.5L) cups to build a massive root system before going into the garden.
- 🧪 Fertilizer Mistakes: Never use “Bloom Boosters” (like MKP) on baby seedlings! They need Nitrogen for leaves and Calcium for cell walls, not massive doses of Phosphorus intended for fruiting.
- 💧 Helicopter Watering: If you keep the soil constantly wet, the roots have no reason to grow. Let the soil dry out slightly so the roots are forced to stretch and search for water.
I picked my best non-grafted eggplants to compare them with the grafted ones. See the photos below. The cotyledon leaves are naturally falling off both of them now. Even without me telling you, you can easily guess which ones are grafted and which ones aren’t…
And the funny part is, I used the absolute worst, weakest seedlings as scions for the grafting process! Now they have completely overtaken the others. 😯
(Non-grafted)
(Grafted)
Now we just have to wait for the final harvest results! ✍️
They are all in 16 oz (0.5L) cups right now, but they desperately need to be moved to 32 oz (1L) pots… 🤦♀️
Tatunya (Tanya) wrote:
They are all in 16 oz (0.5L) cups right now, but they desperately need to be moved to 32 oz (1L) pots… 🤦♀️
Tanya, your eggplants are gorgeous! 👍 When did you plant them? Mine are still so tiny.
Tatunya (Tanya) wrote:
When did you sow yours?
I started them in a little plastic sauce cup on Feb 24th. Moved them to dirt in early March. But I’ve only been giving them plain water. I just started adding a little fertilizer. They just won’t gain any strength or size!
Last year I planted eggplants this exact same tiny size into the greenhouse, and I still haven’t finished eating the harvest. By the way, those were “Grishkevich-style” eggplants, thank you for the recipe @Lenka 🌹 I still have two canned jars of them sitting in the pantry!
natko (Natalia) wrote:
You have to “pot them up” more than once if you want them to grow into absolute horses.
But there’s nothing to pot up yet! Last year they were in 32 oz (1L) pots and they still didn’t grow. When I finally planted them in the greenhouse, half the potting soil fell away because the roots never filled it.
For some reason, my seedlings at home just refuse to grow roots. The soil is good, and last year I even watered them with MKP (Monopotassium Phosphate). I just can’t get a good root system. When I used to grow seedlings at my office window, I never had this problem. It’s a mystery to me.
Galiy (Galina) wrote:
…last year I even watered them with MKP (Monopotassium Phosphate).
Galya! MKP is used during flowering and fruit set! For young seedlings, you should be alternating between Calcium Nitrate and a humic acid complex. (And this is coming from a person who rarely fertilizes seedlings at all! But my starting soil is very rich).
Galiy (Galina) wrote:
When I used to grow seedlings at my office window, I never had this problem. It’s a mystery to me.
What mystery?! At the office, you have completely different “Capricorns” walking around than you do at home! 😂
For some reason I’m drawn to making jokes today… must mean the warm weather is finally coming! 🌹
Galiy (Galina) wrote:
But I’ve only been giving them plain water.
Hm, we really need to find the root cause. Is it the soil? I haven’t fed mine a single time yet, though I probably should. Hopefully I can squeeze in at least one feeding before planting them in their permanent beds…
natko (Natalia) wrote:
You have to “pot them up” more than once if you want them to grow…
Not necessarily. I kept some eggplants in tiny 5 oz (150ml) cups way too long. I couldn’t find the photo, oh well. But the second I finally potted them up into 16 oz (0.5L) cups, they instantly filled the whole volume with roots.
Galiy (Galina) wrote:
When I used to grow seedlings at my office window, I never had this problem. It’s a mystery to me.
Could it be because of this:
At work, you are with the seedlings all day and you monitor them, but you don’t have time to mess with them because you have to actually work. At home, you coddle them. The second you think they look a tiny bit dry, you water them. Why would their roots grow if there is constantly an abundance of moisture and a lack of oxygen in the soil? Roots only grow when they have to actively search for water and nutrition! Another reason could be that you packed the soil down too tightly.
Also, I don’t give my seedlings MKP (it has Potassium without Nitrogen to balance it, which can block the uptake of Magnesium and Calcium). Instead, I use a Superphosphate extract (steeping it in boiling water). Both the plants and I love it. The young leaves come out beautiful—tender and light green.
Galiy (Galina) wrote:
Mine are still so tiny.
Galya, first of all, you absolutely must transplant them into 16 oz (0.5L) cups. Use very loose soil, and don’t fill the cup all the way to the top. Try not to disturb the roots, just move the whole dirt plug.
Put a box or something similar on your windowsill to elevate the cups higher so they get more light and sun.
Immediately after repotting, feed them with Calcium Nitrate (about 1/2 teaspoon per 1 quart of water / 2g per 1L). Add 2 tablespoons of that solution on top of the moist soil. Three days later, feed them with a balanced complex fertilizer, like a 20-20-20 blend, using the exact same ratio as the first feeding. Everything will take off after that!
Valtwelve (Valery) wrote:
At work… you don’t have time to mess with them. At home, you coddle them…
It’s actually the exact opposite regarding the environment! My old office had massive, warm, South-facing windows covering the entire wall. It was on the 3rd floor (but technically as high as a 5th floor). Wide, warm wooden windowsills. And absolutely no shade, no trees blocking the light, nothing in the way.
My house is on the 2nd floor, surrounded by huge shade trees, and the windowsills are half the size.
And I definitely don’t coddle them. I don’t even need a huge harvest, there aren’t enough people to eat it all! But I have to maintain the summer house, mow the lawn, and keep things growing. I just can’t bring myself to throw away extra seedlings. As a result, I end up crowding them and harming the good tomato plants. 🤦♀️
Tatunya (Tanya) wrote:
Is it the soil?
The soil is good, I got it delivered from Leroy Merlin. Tested it out last year. The 2nd floor shade is the only logical explanation left in my head.
Galiy (Galina) wrote:
The 2nd floor shade is the only logical explanation left in my head.
I still have a lingering thought that maybe you watered them too often and the roots were suffocating?
Aleksan9ra (Ludmila) wrote:
Galya, first of all, you absolutely must transplant them into 16 oz (0.5L) cups.
I repotted them. There were barely any roots. Oh well, let them grow! I do really like using those plug trays for growing cabbage seedlings, though. 🙇♀️ Thank you for the advice, Ludmila! 🌹
Tatunya (Tanya) wrote:
I still have a lingering thought that maybe you watered them too often and the roots were suffocating?
Actually no, I always waited until they were dry. I was terrified of drying them out completely, but I know my own weaknesses so I tried very hard not to overwater them. 😎
👨🔬 Editor’s Botanical Note: Stop Giving Seedlings Bloom Boosters!
Galina’s struggle with her eggplant roots brings up two incredibly important rules for indoor seed starting:
1. The MKP Mistake: Galina mentions she fed her tiny seedlings MKP (Monopotassium Phosphate, 0-52-34). This is a massive mistake! MKP is a highly concentrated “Bloom Booster” designed to stop a plant’s vegetative growth and force it to produce flowers and fruit. If you give high doses of Phosphorus and Potassium to a baby seedling, it will completely stunt its vegetative growth. Seedlings need Nitrogen (for green leaves) and Calcium (for building strong cell walls). Stick to balanced fertilizers (like a 20-20-20) or Calcium Nitrate for babies!
2. Roots Follow the Water: Valery drops a golden rule of horticulture: “Roots only grow when they actively search for water.” If you constantly keep the soil in your seedling cups perfectly moist (helicopter watering), the roots have absolutely no reason to stretch out and grow. They will stay small, lazy, and clustered at the top of the pot. You must let the top layer of soil dry out slightly to force the roots to dive deep in search of moisture!
