I had one jalapeno plant. It died, and I had some of its peppers left over. At the time it died, it was 1.5 feet tall and was planted outside, so it died from cold. It was about 6 months old. I planted its left over peppers and got two new plants. They're about 5 months old. One is about a foot tall. The other is about 4 inches. The second one had a lot of light obstruction from the first one. They are indoors and get light from a light bulb situated above them. The bulb is on a timer and turns on and off at certain times of day. They get about 14 hours of light per day, and it's a common LED bulb about 1.75 feet away from the bulb. The taller plant has just begun budding, and its buds are tiny (about 1 mm long, barely noticeable). The other one is not. I've read that it takes about 3 months for them to get to 3 feet and start budding. Is it just really slow growth, or does it have bad genes and won't grow very tall? I got it at walmart and it was labeled "giant jalapenos" and its parent plant had very large peppers but was quite short. The parent plant continued growing months after it started budding. How tall might my new plants get?
Question About My Jalapeno Plants (and Their Underperformance)
Certified GKH Gardening Expert
There are a whole lot of issues to address here. So, Jalapeno flowering is directed by temperature. When the temperature remains pretty close to the same from day to night, then the pepper will start flowering, and focus less on vegetative growth. In order to increase the growth of your peppers, they will need a variation of about 10 degrees or more between day and night temps.
Now, the seed stock. These, coming from a supermaket pepper, will not be true to seed. They are usually open pollinated, and will produce an unpredictable array of shapes, flavors, and heat intensity. Multiple grains of pollen from multiple plants can pollinate a single flower, making it almost impossible to control the next generation seed. You will not be able to predict the growth patterns from seed to seed. They will not be stable.
If you are using a household LED bulb, at 100 watts equivalence, and with the bulb cover cut off, then you can expect to light a single pepper plant that is no more than a foot tall, or several seedlings. The bulb cover drastically reduces the amount of light produced.
After this point, they will need to be outside, or under about 200 watts per plant with a high end LED, or 150 per plant with HID horticultural lighting.
One more thing to address is the feeding requirements. Peppers are VERY heavy feeders. They will require, either, liquid feeding once every two weeks, or compost added once per month.