Some hot peppers are surprisingly easy to grow, in my experience. Like having fresh herbs growing in the backyard, having a robust serrano or jalapeño plant in a pot certainly enlivens my cooking (and pickling!).
Both serranos and jalapeños get hotter as the season progresses and the jalapeños get thin brown scars (see photo at left) and both eventually turn red. They can be very spicy, though I find it really varies. Typically the more scars they have the hotter they are. They also have a rich flavor that adds depth as well as heat to salsas, soups and sauces.
The Czeck black pepper is typically a little less spicy than a jalapeño. It has juicy, thick flesh and thin skin and turns from black to bright red later in the season. It’s great for pickling or salsas, soups, and other dishes.
Cayenne peppers are the spiciest of the four discussed here. They are wonderful pickled and commonly used in hot sauces or dried and ground. You can use them fresh wherever a little heat is needed. They are delicious chopped and mixed with a little butter or aioli and spread on a sandwich. I often use the dried ones by removing the seeds and breaking the pepper into 2 or 3 pieces and sautéing it with whatever vegetable or meat I might be cooking and then removing the pieces. I do the same with curries and pots of beans. The pepper will impart quite a bit of heat but a bit more subtly than by leaving it in the dish.
Take care handling all of these peppers but especially the cayennes and be sure to wash your hands well before touching your eyes. All of these peppers keep quite well, often for several weeks in the refrigerator. The cayennes of course can be dried as well and then have a much longer shelf life.