Peppers 2025

[Branching Out]

Mid-January, and a couple of Siracha plants that are growing outdoors under cover are still ripening fruit. I picked all of these a couple of days ago. That was a welcome development, but it's not at all typical for our area. We're having an unusually warm, wet winter this year.

Over the past few years I've had some challenges starting pepper seeds, and I would like to find a method that will give me better results. So recently I've been doing a bunch of pepper germination experiments. This photo shows seedlings grown using seeds of a red bell pepper that was purchased at the grocery store. My experiment was to see if germinating the seeds at a slightly warmer temperature really makes much of a difference. I'm re-reading Nancy Bubel's book The Seed Starters Handbook, and she mentioned that not only do the pepper seeds germinate faster-- but the resulting seedlings are less likely to be deformed, or stunted. Well this little experiment certainly supports that theory. Initially I put 20 seeds in each cup. The container on the left went in a humidity dome on a heat mat at about 24C(75F), and the container on the right was left at room temperature to germinate (in our house 'room temperature' is about 20C(68F) during the day, and 17.5(63.5F)C at night time). At the two week mark there wasn't a very big difference between the development of the seeds in the two containers, but by the three week mark when I took this photo the difference was dramatic. I am quite shocked at how much healthier the seedlings look when they begin life with just a few extra degrees of heat. I think I'll repeat this experiment using some of the Siracha seeds, to see if I get similar results.

 

[flowerbug]

i'm drooling over the fresh peppers...

 

[digitS']

You may have to wait a little while, @flowerbug .

Here is the Easy (dang near too easy):
Seeds for all warm-season plants are started in our kitchen. My old-style refrigerator would generate a fair amount of heat and warm the top and on into the cabinet above, keeping the temperature up through the night. The new-style fridge doesn't make that much heat but it's still the warmest location overnight and through the day.

When "green" appears above the soil surface, the plants need to migrate out to a  sunny South Window. It is in the coolest part of the house without ample sunshine and the outdoor weather certainly doesn't cooperate at times. At one time, I increased the amount of light with a large fixture above that table. It was a bother and did little for heating.

For limited light, limiting heat is best. One cannot substitute for the other. Plants perform better with abundant light even if temperature is somewhat low, by whatever requirements a specific species has. Peppers have such obvious higher standards than this make-do situation affords. I can pamper them by keeping some of them toasty in greenhouse through the Summer. It helps.

Steve

 

[ducks4you]

That is SO true. I remember starting tomatoes downstairs in my "cave temperature" basement and they grew just fine without a heat mat. And, I posted on my thread that I just heard advice about no heat mat for alliums.
Shucks, I have chickweed growing in my basement cement window wells!!! All they get there is sunlight!

 

[digitS']

Something that may make peppers a unique garden plant, and they certainly are, is that they are perennials.

While we might think of them as demanding, they make up for it by being tough during more mature stages of their growth. Defenseless as infants, they are mercilessly attacked by aphids. I think that they must have a negotiated relationship with ladybugs .

I was reading about another Solanaceae, the Tropical Soda Apple. Apparently, it is not all that tropical. Now classified as an invasive, it wasn't even in the US 40 years ago but now grows as far north as Pennsylvania! Unlike the capsicum species, it does this entirely on its own.

digitS'

 

[R2elk]

Something that may make peppers a unique garden plant, and they certainly are, is that they are perennials.

They may be perennials in your zone but they are not perennials here.

Tomatoes in a warm enough zone can also be considered perennials.

 

[digitS']

Oh no, @R2elk

I'd have to do more than allow them to perish in the unheated greenhouse.

They are perennials in the tropics.

 

[flowerbug]

You may have to wait a little while, @flowerbug .

Here is the Easy (dang near too easy):
Seeds for all warm-season plants are started in our kitchen. My old-style refrigerator would generate a fair amount of heat and warm the top and on into the cabinet above, keeping the temperature up through the night. The new-style fridge doesn't make that much heat but it's still the warmest location overnight and through the day.

When "green" appears above the soil surface, the plants need to migrate out to a  sunny South Window. It is in the coolest part of the house without ample sunshine and the outdoor weather certainly doesn't cooperate at times. At one time, I increased the amount of light with a large fixture above that table. It was a bother and did little for heating.

For limited light, limiting heat is best. One cannot substitute for the other. Plants perform better with abundant light even if temperature is somewhat low, by whatever requirements a specific species has. Peppers have such obvious higher standards than this make-do situation affords. I can pamper them by keeping some of them toasty in greenhouse through the Summer. It helps.

i do have a heat mat i just don't have any good place to put it right now and likely for the next few months...

i'm going to be really busy with beans and getting prepped for giving things away and sending out some packages. that's plenty enough...

 

[Zeedman]

Peppers really need more heat to germinate reliably - especially with older seed, which is often what I am using. I've documented my germination results in past threads.

Tomatoes are more tolerant of cooler temperatures, and I see little variation in germination days or vigor, even between new & old seed. Tomato seed also has a much longer storage life than peppers.

Pepper seed is much more sensitive to soil temperature, and even the difference between 70F (20C) and 80F (26C) can make a big difference in germination. I used to start seeds under lights at room temperature; some peppers might take 3-4 weeks to germinate, and then poorly, often with weak seedlings. When I began using heat thermostatically regulated to 80F, germination was still variable, but less so; and I'd estimate the average was 5-7 days faster. More importantly for me, the germination rate was much better for older seed.

As @digitS' mentioned, the old-style refrigerators (those with coils on the back) were a good place to germinate seeds. They are warmer on top than the rest of the room, due to warm air rising from the coils. But my new(er) fridge has the cooling soils on the bottom, with a cooling fan - so the top is cooler than the room (I store my flour there for that reason).

You can also increase the germination rate of peppers (and almost any annual seed) by watering the first time with a light nitrogen-containing fertilizer solution. This is especially helpful with older seed.

 

[Zeedman]

For limited light, limiting heat is best. One cannot substitute for the other. Plants perform better with abundant light even if temperature is somewhat low, by whatever requirements a specific species has. Peppers have such obvious higher standards than this make-do situation affords. I can pamper them by keeping some of them toasty in greenhouse through the Summer. It helps.

Agreed. Warm temperatures, with dim light, tend to result in leggy plants.

The different pepper species have differing light requirements. C. annuum (sweet peppers & many hot peppers, such as jalapeno) need the most light. C. baccatum & C. frutescens peppers (mostly hot peppers) need less light. In my experience, those do better than C. annuum peppers under lights (and will tolerate some shade outdoors).

It's worth noting that the C. frutescens peppers (such as habanero) can have very temperamental germination, sometimes 3-4 weeks or more. They are also slow growing, so if I grow one of those, I start it several weeks before the others, and always with heat.