Are your pepper seeds not germinating, or sprouting erratically? Don’t worry, you’re not alone. Peppers are notoriously hard to germinate because of their desire for tropical conditions.
Thanks to years of trial and error, we’ve got some tips and tricks to germinate peppers more effectively, and hopefully some answers as to why your pepper seeds aren’t germinating.
The most common reason that pepper seeds don’t geminate:
By far the most common reason that peppers fail to germinate is early sowings. Our instincts as gardeners trigger us to try to get a head start on the seasons but unlike tomatoes, alliums, and beans, peppers should always be sown right at the end of spring, once the days equal the nights.
At an absolute minimum, peppers need at least eight hours of sunlight per day to trigger germination. You can trick them into an early start with full-spectrum grow lights, but peppers find their own rhythm.
When to sow peppers for reliable germination:
- After the spring equinox
- USA: mid to late-March
- Northern Europe: late-March
- Southern Europe: mid-March
- Sow peppers when indoor / greenhouse temperatures are reliably over 18°C/64°F
- When there is a minimum of 8 hours per day of direct sunlight
Why are my pepper seeds not germinating?
While early sowing is the most common reason for germination failure, it must also be said that peppers are very susceptible to damping off, have fungal disease at the germination stage, and dislike erratic temperatures.
Other reasons that your peppers might not be germinating include:
- Damp soil (too far from their tropical conditions)
- High calcium levels in water (this dehydrates seeds)
- Erratic temperatures (peppers need regular heat, so should be germinated on a heat mat, propagation tray, or a bright windowsill without drafts)
- Low light levels (sow peppers in a bright location, or boost their UV exposure with full-spectrum grow lights)
- Old seeds
How long does it take for pepper seeds to germinate?
In ideal conditions, peppers will germinate in 7-10 days but have patience. Provided they are not waterlogged, or dehydrated pepper seeds can still sprout up to a month after sowing.
Are your pepper seeds too wet?
Remember that pepper seeds prefer tropical conditions. These habits have never been bred out of them as the fruit ripens with a much sweeter flavour in hot, direct, sunlight. The same goes for their seeds. If your pepper seeds are sat in damp compost they will more than likely develop fungal problems that either stop germination or create problems with seedlings.
To water pepper seeds before germination, water once when you sow, and only water if the soil is dry on the surface. Water again lightly when you see signs of germination.
Providing the right heat and light to germinate peppers
One common reason that peppers fail to germinate is low temperatures or erratic temperatures. Their seeds require at least 8 hours of sunlight or grow light, exposure, and regular temperatures of 18°C/64°F to guarantee pepper germination.
Do old pepper seeds germinate?
If you consider the Millennium Seed Bank at Kew Gardens, UK, it’s entirely possible that any seed, from any plant, can germinate no matter how old it is, provided it is properly stored. However, in unopened seed packets stored in normal dry conditions peppers seeds are only really viable for 2 years.
If you’re trying to germinate old pepper seeds it’s likely that under perfect conditions you might get a 20% success rate, but any more is unlikely. Also, keep in mind that sowing pepper seeds from grocery store peppers will be equally unreliable. Both are possible but will take a few good tricks to get reliable germination.
Tricks to get pepper seeds to germinate
Peppers are particularly picky about how, when, and where they will germinate, but there are some great tricks to germinate peppers that we’ve learned through the years:
- Soak your seeds in lukewarm chamomile tea
- Use purified water or bottled spring water
- Use a heat mat & grow lights
- Don’t cover your pepper seeds with soil
1. There are two benefits to soaking pepper seeds in chamomile tea. The first is that the tannins help to soften the thin seed casing, making germination faster by 1-2 days. The second reason is perhaps more useful; Chamomile tea is mildly antiseptic, which means it actively prevents damping-off in your young seedlings when they do germinate.
2. Pepper seedlings watered in with bottled water do have a better success rate than those germinated with tap water. Unlike houseplants, you don’t have to continue using distilled water once they germinate. The initial impact of the calcium in tap water can dehydrate pepper seeds before they germinate.
3. If you haven’t used a heat mat or heated propagator to germinate your peppers, this is one of the most common reasons indoor peppers won’t germinate. They require temperatures of at least 18°C/64°F to germinate, so throughout colder regions, it’s essential to keep them at a regular temperature. If you don’t have a propagator, keep them on a windowsill above a radiator, or on top of the fridge (if there is enough light).
4. To boost the light levels for peppers, consider how their seed would naturally be spread. Tropical birds adore capsicum (the chemical that gives chillies their heat, and peppers their flavour) so seeds are spread in droppings and land on the soil surface. Copy this at home by sowing peppers in seed trays, and either don’t cover them or just cover lightly with vermiculite so they get maximum sunlight.
How to care for pepper seedlings
Once your peppers have germinated, they’re still not out of the woods! Peppers need care and attention right through the growing season, so we’ve put together a guide on how to spot and treat pepper seedling problems to help you on the next step of your journey.
Once you’ve successfully germinated your peppers, and they’ve developed their true leaves, they’re nearly ready for transplanting. Read our guide on how and when to transplant pepper seedlings to bigger pots and then just keep them well-watered and well-fed with a standard tomato feed.
As long as your mature pepper plants are properly fed and watered, and kept in full sun behind glass you’ll be eating bountiful harvests all summer as young peppers quickly grow to replace the ones you pick early in the season.
Final thoughts on pepper seeds not germinating (don’t be afraid to start again!)
While it’s indisputable that peppers are hard to germinate, they do surprise us sometimes. In one particularly hot spring (2018) we found peppers sprouting in our garden in May, and got a full harvest from Loco F1 chilli peppers in summer without any covers.
Once you know how to germinate pepper seeds, you’ll never look back, as growing your own peppers can save you money on your grocery bills, and other than a few helping nudges, they don’t need that much attention. Hopefully, with these tips and tricks, you’ll never have trouble with pepper seeds not germinating again!