I planted some Serranos back in mid may, and at first I thought everything was going great. But after a while they began to slow down and appear to have gone leafy. Friends have planted later than me and their plants have started fruiting already where mine is still quite small.

I was wondering if there is actually any wrong with it or am I over thinking.

For reference I repotted a couple weeks ago using an even mix of perlite and vermiculite. with this soil: https://www.amazon.co.uk/gp/product/B008JCW25W/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

And I am using this light: https://www.amazon.co.uk/gp/product/B07K2TW1G2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I have (up until the last few weeks) been feeding them weekly with Chilli Focus which I think could possibly be part of the problem as the soil comes pre-enriched with a 20:20:20 fertiliser.

Does anyone know if they're alright or should I change my setup?

Side view Normal light


3 Answers 3


Sure looks healthy to me, Tom! Please tell us what you have added for fertilizer and at what stage did you add a balanced fertilizer of NPK. I am glad you used potting soil. The pot and soil are too large for this size plant but that is not harming this pepper. In the future, seeds go into tiny pots 1" wide by 2", no larger, roots show then up pot to 3 or 4" wide pot, roots show up pot to a 6" or 1 gallon. All with potting soil. Fertilizer should begin about the 2nd or 3rd set of true leaves. Use half of what the directions tell you. If you used high N (10-8-7) you'll get lots of vegetative growth.

By adding a fertilizer with equal or lower N in relation to the percentages of P and K, you will be 'telling' this plant to think about reproduction.

Small plants in big pots work on roots. Plants fitted to their pot in size switch sooner to top growth. The way to make reproductive growth is by Low N in relation to the P and K: 2-5-4 Growilla. I start out with 5-5-5 after the 3rd set of true leaves. If and when plants show signs of fertilizer deficiency I switch to Growilla to up the reproductive growth.

Making one's own soil where that soil you mixed with the perlite and vermiculite with 20-20-20 is very high fertilizer and to add more I am amazed you don't have fertilizer burn.

Your light is good. I would get a fan blowing 24/7 keep the air moving. That also moves the new O2 and H2O away from the leaves so that CO2 can be uptaken for photosynthesis. Also inhibits fungal disease such as powdery mildew. Plants that are over fertilized, look very very green and are susceptible to fungus, very attractive to sucking insects.

IF THIS truly is over fertilization, which it sure sounds like, I would REPOT this plant into a 6" or 1 gallon pot with cheapo sterilized potting soil with no fertilizer or other gimmicks added (water holding sponges and gels, ugh). To be in charge of the fertilize you have to be the only one who adds fertilizer.

I haven't been able to look at your sites as yet. You've really done a lot of work here and Peppers grow so well and prolifically under lights. I'll go look at this soil and be back.

What color of light spectrum are your bulbs? Blue or Red? Red is for reproduction.

Additional: Tom, I went and tried to find the ingredient label or any details about this compost/coir.

I like that they didn't use peat moss. Very good.

They did not say what 'nutrients' were in that soil but you said the chemistry (not nutrients) was 20-20-20? These numbers mean percentages of the product, so a bit confusing. This block just could not be 60 percent fertilizer!

Do you have availability of plain old sterilized potting soil? Nothing added? I'll look up your fertilizer you are adding weekly??

Another dead end. I have no idea what the percentages are. I am fairly sure you have over fertilized. Your plant is not FRIED, looks healthy. I would repot and not add any fertilizer at all. Change my bulbs to red spectrum. You've got LEDs, yes? You will have to wait a good month to see peppers, I think. Also, you need to think about pollination. You can pollinate the flowers by yourself. I would use a small artist's paint brush. You can also shake the plant now and then.

Please send more information, you've done a great job with what you have sent but I am still assuming an awful lot.

  • Hey, thanks for the detailed response! amazon.co.uk/Growth-Technology-Ltd-05-210-110-Concentrated/dp/… is the fertiliser that I have been using, and I believe I started using it around the time the second set of leaves started to grow. I'm just quoting the listing page for the soil, which says 'Npk 20.20.20 fertilizer blend which is widely used by growers and professional gardeners.' I mixed the vermiculite and perlite at 1:1:10 with the soil. Also, I forgot to mention I do have a small USB fan that I keep on the majority of the time
    – Tom Bass
    Aug 6, 2019 at 17:43
  • And yeah LED lights with both blue and Red. Do you think it would be a good idea to shift to Red at this stage? Thanks again
    – Tom Bass
    Aug 6, 2019 at 17:50
  • I'd prefer not to repot it again unless I have to, I haven't fed it since repotting it in the new mix, it just had the nutrients that came in the soil.
    – Tom Bass
    Aug 6, 2019 at 17:57
  • 1
    Since your plants look very healthy, "Don't fix it unless it's broke" makes sense. You aren't over watering. No need at all for MORE balanced fertilizer. The lighting is great and I am glad you are using a fan! You get this stuff and are doing just fine. When transplanting into new soil and a new pot that always sets the plant to working on their root systems, not the top growth. Slows the process down a bit. Are your practices the same as your friend's? Definitely switch to red lights if you can. I call fertilizer chemistry, not nutrients. People, not you, think fertilizer is 'food'.
    – stormy
    Aug 6, 2019 at 19:01

Fertilizing every week is a lot, even if your soil doesn't come pre-fertilized. Generally, people do it every two or three weeks at the most (and many do it a lot less).

The soil might be too salty from all the fertilizer salts.

I would just hold off on the fertilizer for a good while. It's probably got plenty to supply it.

You may want to increase the temperature a bit, too, to make the phosphorus in the soil more available. I notice your internode length is very short. Phosphorus helps to promote plant maturity, I believe flowering, and it also helps the internodes to stretch out more. Some greenhouses who grow plants to sell use low phosphorus and I believe cool temperatures to prevent leggy plants. However, if you want fruit, you probably would be better off with your phosphorus being more available.

  • I agree with the amout of fertilizers. People use them way too much. I have two habaneros which I planted from seed in early March. I've replanted them twice since (now in 21cm pots) and fertilized with dried cow shit every time I replanted them. Not more. They are about 80cm tall each, fully healthy plants which are now starting to blossom.
    – Fatmajk
    Aug 6, 2019 at 9:15

You need to cover the roots a bit better, with another - at least - one inch of potting mix. For the root ball to be exposed like that is not good. What is your watering schedule? If she (ie. your plant) is getting daily light exposure she will need plenty of water. Finally, fertilising her with a good fertiliser like Osmocote will help her thrive, grow and flower, then bear fruit. Does she get any natural sunlight at all? Probably should make this a priority, behind glass if you are in a cold country. All the best :)

  • Hey, The root system is a good few inches below the surface, what you see there is the coconut husks from the potting soil :)
    – Tom Bass
    Aug 6, 2019 at 17:51
  • I do have a window, but it gets very little sunlight so I think its probably for the best that I keep them under the artificial light for now. Thanks for the fertiliser suggestion!
    – Tom Bass
    Aug 6, 2019 at 17:52

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.