The Double Cup Method

To grow hot peppers using the double cup method, you will use 2 Solo cups per plant, one inside the other. The outer cup acts as a water reservoir. The roots will grow out of the inner cup and dangle into the water of the outer cup. This prevents the roots from becoming root bound which can be a problem with pots. Also, because the soil is not getting wet, you reduce your chances of harboring insects like gnats and developing fungus or disease. Watch the Video below!

hot pepper double-cup roots

Double Cup Materials

  • 2 Solo cups per plant. 18oz cups are preferred but you can get away with 16oz. (you can also do one square bottom cup & one round bottom*). They don’t have to be Solo brand. No clear cups.
  • Soil. Suggestions below.
  • Stakes. I like these at Home Depot or these on Amazon. Wooden popsicle sticks tend to absorb water and get moldy.
  • Seeds. You do have seeds right?
  • (optional) Pizza savers (video below) *not necessary if using square/round bottom cups.

The Best Soil For Hot Pepper Plants

I recently did a study comparing FoxFarm’s Ocean Forest vs Happy Frog soils (among others) and the results might shock you! I won’t spoil the surprise, but I discovered that these soils do not require fertilizer (while they are indoors)! That’s right, no need to spend time and money on fertilizing your plants indoors. This is a HUGE benefit that (in my opinion) definitely justifies the price. I was also able to germinate seeds in these soils too.

bag of ocean forest soil

Happy Frog is a little cheaper than Ocean Forest but either will do. Or you can do a mix of both! For Long Islanders, check out Agway in Mt. Sinai.

bag of happy frog soil

Other Soil Options

I used ProMix in 2021 with good results. I did need to fertilize however. You can also make your own soil by mixing some organic compost or potting soil with a little bit of perlite. I like to get a 5lb bucket and fill it 3/4 with compost and add about a solo cup of perlite. Perlite helps with water drainage. If you use straight compost it will compact and water will not flow through. And if you use too much perlite the water will flow through the dirt too quickly 🙂 I stay away from top soil since it is far too dense and tends to harden.

Check to see if the soil you use contains fertilizer and if it doesn’t, you’ll need to add your own.

Labels & Stakes For Hot Pepper Plants

You can write on your stakes with permanent marker. Or, if you want to reuse your stakes year after year, you can print the plant species on these waterproof labels. Make sure you use a laser printer; an inkjet printer ink will run when they get wet.

I like these stakes the best because you can sink them deep into the soil. These, on Amazon work well too. Some people write on upside down plastic spoons too. I wouldn’t suggest wooden popsicle sticks since they tend to absorb water and get covered in white fuzzy mold. Keep in mind, any color other than black will fade in direct sunlight.

ALWAYS take pictures of your plants throughout the season. This way if your labels get misplaced or the ink fades you’ll know what they are!

How to Start Pepper Seeds in Double Cups!

*Video Updates

*If the soil you choose doesn’t contain fertilizer you will need to add it yourself either to the soil or in the water of the outer cup.

*Push the seeds in about 1/2 inch into the soil, otherwise they might sprout with the shells stuck on their heads, a.k.a. “helmet heads” lol.

*Only water the soil if your soil contains fertilizer. If you are adding fertilizer to the water in the outer cup then you don’t need to get the soil wet at all.

Separating the Double Cups

The cups will nest inside each other with the dirt in the inside cup and the water in the outer cup. You’ll need to find a way to prop up the inner cup so that there is a 1-2″ gap between both cups. Some people put rocks in between. Some people use a Solo cup with a square bottom for the dirt and a cup with a round bottom for the outer cup. Or – use pizza savers!

Using pizza savers to create a space between your cups!

Best Temperature For Hot Pepper Seeds

Put them in the warmest room of your house. Hot pepper seeds germinate best when the soil temp is between 65-95 degrees, 80 being the optimal soil temperature. You can use a meat thermometer to check the temp (remember to wash it afterwards :). You can also use heat mats to raise temps by 10-15 degrees if you need the extra warmth.

Watering Hot Pepper Seeds

Check on the seedlings once a day. Make sure the soil has not dried out. Make sure it is moist, not wet. Moist! I use a spray bottle (or even a turkey baster). I reuse an empty gallon (milk, iced tea) jug, fill it with tap water, and let it sit for 24 hours uncovered to allow the chlorine to evaporate and the water to come to room temperature. I adjust the water to a PH of 6.5.*

*Adjusting the PH of the water isn’t really necessary for plants that will live inside for only 2 months, but I do it because I’m a nerd. Once the plants go outside I let nature take over.

Do Hot Pepper Seeds Need Light?

They don’t need light until they start to sprout. When they do sprout you will need to start giving them light asap or else they will get tall and “leggy”.

How Long Do Hot Pepper Seeds Take To Germinate?

In optimal conditions you can expect germination in about a week or so. Superhots, like the Carolina Reaper can take around 2 weeks (and some up to 4 weeks!) so be patient. It’s very exciting to see the little sprouts emerge from the soil (right?). Typically for me, if I do not see sprouts in 10 days I will start another tray as a backup. You don’t want to wait too long in case you screwed something up since starting over at this point is going to take away from your growing season.

page updated 7/22/22