Gadenin日本語Get the appCount backwards from your first ripe pod, not forwards from sowing
The very hot small-podded chillies are late. Where a sweet pepper goes from sowing to a usable green fruit in about four months, the fiery sorts want five to seven months to reach full color, and color is where nearly all their heat and flavor sits. Picking them green throws away the reason you grew them.
So the sowing date is decided by the end of your season, not the start. Work out the week your nights reliably fall below 50F (10C) in autumn, subtract six months, and sow then. In a short summer that puts the tray on a windowsill in the depths of winter, which feels absurd and is nonetheless correct.
| Type by heat | Weeks from sowing to first ripe pod | When to sow relative to last frost |
|---|---|---|
| Mildly hot, thin walled | 16 to 18 | 8 weeks before |
| Hot small pods, upright | 20 to 24 | 12 weeks before |
| Very hot, wrinkled, thick skinned | 26 to 32 | 16 to 20 weeks before |
| The slowest of all, hairy leaved kinds | 30 to 36 | 20 weeks before, or overwinter a plant instead |
If the arithmetic says you should have sown two months ago, do not sow anyway and hope. Buy in a plant this year, and instead carry one healthy plant through the winter so that next season starts with a two year old frame already in leaf.
Bottom heat is the whole battle
Seed of the fiercest chillies is the slowest and fussiest of the lot. It wants the compost itself held at 82 to 88F (28 to 31C) around the clock. Air temperature in a warm room is not the same thing: an unheated tray on a windowsill often sits a full ten degrees below the room, and at 68F (20C) most of this seed simply rots before it can emerge.
Give it steady bottom heat and the first shoots break in eight to twelve days, with the stragglers up by three weeks. Without it, expect four to six weeks, patchy emergence, and a batch you write off too early. Do not throw a tray away until day 35.
- Sow shallow into damp, fine compost A quarter of an inch (5 mm) deep, one seed per cell, in a fine seed-starting mix watered the day before so it is damp rather than wet. Deep sowing costs several days of energy the seedling does not have to spare.
- Hold the humidity, not a swamp A clear lid or a bag over the tray keeps the surface from drying and crusting. Lift it for a minute each day so the air changes, and take it off entirely the hour the first shoot appears.
- Put the probe in the compost Push the thermometer probe into a spare cell rather than leaving it lying on the bench. You are managing the temperature the seed feels, and that is the only reading that matters.
- Resow the gaps once At day 14, sow a second seed into any cell still empty. It costs nothing and evens out a batch where a third of the seed was slow.
Light, the moment they are up
Germination heat and growing light are two separate jobs, and the mistake is to leave a germinated seedling on the heat mat in poor midwinter light. Warm and dim gives you a pale stem three inches (8 cm) long with two leaves on top, and that plant never recovers its shape.
The moment the loops of stem straighten, the seedling wants the brightest place you have and slightly cooler air, around 70F (21C) by day and 64F (18C) at night. If you are sowing in winter you will need a grow light run 14 to 16 hours a day, held two to four inches (5 to 10 cm) above the leaves and raised as they grow. A windowsill alone in midwinter is not enough for a plant with a six month road ahead of it.
A small fan on the seedlings for a couple of hours a day, or a gentle brush of your hand across them each time you pass, thickens the stems noticeably. Movement is a growth signal, and stocky plants transplant far better than tall ones.
Potting up before the roots circle
These plants spend an unusually long time in pots, which means two or three moves rather than one. Go up in stages: from the cell to a 3 inch (8 cm) pot as the first true leaves expand, then to a 5 inch (13 cm) pot when roots show at the drainage holes, then to the final position or a container of at least 5 gallons (20 liters).
Do not jump straight into a large pot to save a step. A small root system sitting in a big volume of cold wet compost stalls, and a stalled seedling in midwinter loses weeks it cannot make up. Feed at quarter strength from the second pot onwards, weakly and often, because the plant is in that compost for a long time.
| Sign on the plant | What it means | What to do |
|---|---|---|
| Roots at the drainage holes | Ready to move up | Pot on within the week |
| Lower leaves yellowing evenly | Feed exhausted in the compost | Weak balanced feed at every watering |
| Purple stems and stalled growth | Too cold at the roots | Raise the pot off a cold sill, warm the air |
| Long gaps between leaf pairs | Not enough light | Move under a light, or closer to it |
| Flower buds on a small plant | It is pot-bound and panicking | Pinch the buds off and pot on at once |
Hardening off takes longer than you think
A plant raised indoors for four or five months has soft leaves that scorch in a single afternoon of direct sun. Give it a full fortnight of gradual exposure, starting in full shade outdoors for an hour and building up, and skip the days when the wind is sharp.
Do not put these plants out until the night temperature stays above 55F (13C) and the soil has reached 65F (18C). Cold nights early on check the plant so severely that it sulks for a month, and with a crop this slow to ripen a lost month is the difference between full color and a plant still carrying green pods when the frost arrives.
What to write down this year
Record the date you sowed, the date the first shoot appeared, and the compost temperature you held. Then at the far end of the season, record the date of the first fully colored pod. Those four dates give you the true length of the crop in your own conditions, and next winter you can set the sowing date from your own numbers instead of guessing from a packet printed for somebody else's climate.