Germinating the seeds
Stored seeds don't germinate well, so please deal with them when they arrive.
Getting started -- Your seeds should be given a 6 week cold treatment in the refrigerator for best germination. This tricks them into thinking winter has passed, so they germinate better.
Place the seeds in a small, sealed, plastic or glass container, and fill it with a few ounces (100-200mL) water. Place them in a refrigerator that doesn't freeze (inside the door is usually the warmest part). Mark your calendar to change the water once a week, and remove them after 6 weeks.
After cold-treatment -- Use pots about 3-4 inches tall (8-10 cm) and 3 inches wide, with drainage holes. Alternative, you may plant them all in a single pot, by spacing them 2 inches (5cm) apart.
Use a well-draining soil mix, such as 2 parts potting soil to 1 part perlite or coarse horticultural sand. An alternate mix is equal parts of coir fiber and perlite (use small- or medium-size perlite, not big chunks). You may add some granular fertilizer, but don't add lime to the mix, because they prefer slightly acid soil.
Place a seed in each pot, and cover with a thin layer of soil (1/8 inch / 3 mm) of the mix. Add enough water so the soil is evenly moist, but not completely saturated. If your tap water is very high in minerals ("hard water") it's best to use bottled water or rain water.
Until the seeds sprout, keep the pots between 60-78 degrees F (15-25°C) during the day, and a bit cooler at night (50 to 74°F / 10-23°C). Avoid letting them get above 82 degrees F (28°C). I recommend placing a minimum/maximum thermometer near the pots, especially if using a heat mat. Give them some air circulation to prevent stem rot later. Don't let the soil surface dry out, but don't keep the soil constantly soggy either.
The seeds sprout at different times, usually beginning between 6 and 12 weeks, and continuing for another 2-4 months. Once they sprout, give them bright light, but shade them from strong sun exposure. Water them enough to keep the soil surface from drying out (but again, avoid keeping them soggy). Avoid transplanting them the first year.
Lighting -- Lapageria prefers part sun, with protection from hot afternoon sun. Lapageria likes its roots cool, so try to keep the pot shaded in warmer conditions.
Climate -- Lapageria prefers mild daytime temperatures and cooler nights. It's happiest between about 40 and 85 degrees (5-29°C) with cooler nights (below 65°F / 18°C). Adult plants are said to tolerate down to the low 20s (-5°C) if given overhead protection. But protect your seedlings from frost the first 3-4 years. You may grow them indoors or in a greenhouse provided that the air is cool and over about 40-45% humidity with good air circulation.
Fertilizing -- Seedlings grow slowly the first 2 years and don't need much fertilizer during this time. The first 6 months, feed every 2 weeks with a small amount of dilute (1/8 strength) liquid fertilizer. Hydroponic fertilizer is ideal for seedlings, because it is easily absorbed and contains all essential nutrients. After 6 months, you may switch to a granular fertilizer that contains micronutrients, feeding every 4 months. When growth speeds up after about 2 years, increase the feeding to every 2-3 months, except when temperatures are cold.
Support -- Your seedlings shouldn't need much support for at least 2 years. Older plants prefer to twist around a trellis, fence, wires, etc. Don't prune the shoots. If they get too long, simply wrap them down and around the trellis.
Potting up - When your seedlings are 12-18 months old, they may be gently transplanted to 2-quart (2 liter) pots, which can hold them for 1-2 years, when they can go into a 1-2 gallon (4-8 liter) container, which can hold them until they flower. After another 2 years, you can move them to a 3-5 gallon (11-19 liter) containers.
Pests to watch for -- Protect from snails and slugs, which love Lapageria. Watch for aphids on the new growth, and spider mites under the older leaves (tiny "dots" on the leaves). Scale (small discs) and mealy bugs may appear on the stems or leaves. Try using insecticidal soap before using stronger remedies, since some may harm the plant.
If you have any questions, please email me.
Have fun growing them!
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