The first part of growing chillies is getting the seeds germinated. Most seeds need a consistent temperature. Erratic hot and cold spells aren’t ideal – most germinate in 2 – 3 weeks, however some like the Naga, Habanero etc can take much much longer in our experience!
There are all manner of variables that will affect how long a chilli plant takes to grow.
The core factors we feel are:
the type of chilli plant (the habs and nagas will take longer)
the size of the pot (a small pot will inhibit the plant and limit growth)
the place you are growing it (sunnier spots will help them grow faster)
how often you water and feed (the more regular (though not too much!) the better)
If you are growing a standard pepper, then you can expect the plant to grow to a point where it is flowering in about 8 – 10 weeks