Garden Topics: Starting Plants From Seeds Indoors
It can be enjoyable for any gardener to experience the whole growing cycle as you watch tiny seedlings grow into sturdy plants that bear delicious fruit. It’s also a relatively inexpensive way to grow a wide variety of plants. Many garden favorites are found in a greater variety of colors, sizes and growth habits as seeds, rather than as started plants.
To get a jump-start on the growing season with these easy tips
1. Don't Start too Early
Starting plants from seed isn't difficult once you have the basics. So rule number one: Don't sow too early or your plants will be leggy and overgrown long before you can transplant them into the garden. Seed packets recommend the number of weeks to sow indoors before the average last frost date, For us here in Pittsburgh, the date is 15 May.
2. Deciding what to grow
Annuals and vegetables are the easiest to grow. Perennials, however, are trickier, many require a period of cold to break dormancy and some take a couple of seasons to reach flowering size.
Use only clean containers to prevent disease. If reusing containers, wash with soap, water and a little bleach, and make sure they have drainage holes. Propagation kits and supplies needed for planting are available here at the farm. Supplies include seedling flats, potting soil, tags, tray covers, fertilizer and more. Newly sprouted seedlings may look alike, so label containers as you sow.
4. Sowing medium
Use only fresh, sterile seed-starting mixture. Moisten mixture about an hour before sowing; it shouldn't be soggy, just as damp as a wrung-out sponge.
5. Planting directions
Seed packets contain information on timing, lighting requirements, sowing depth temperatures. Pay close attention to these instructions and follow them. (Note some seed should not be covered) (You may have to soak, scratch, or chill some seeds before planting, as directed on packet) Label/tag your containers before proceeding. There's nothing more frustrating than forgetting what you planted.
6. Keep moisture in
Lightly water freshly sown flats, then cover with
plastic dome lid, or if reusing containers, place them
inside a plastic zip-lock bag. At the first signs of
germination, uncover or remove from plastic bag.
When the top of the soil looks dry, water carefully
using a fine spray. Avoid overwatering: soggy soil and
poor air circulation can lead to damping off, a fungal
disease that can kill young seedlings.
Find a place where there is natural bottom heat. Seeds
sprout best at temperatures of 65 to 75°F, but check the
seed packet for temperature range. When seedlings
appear, remove the plastic and move containers into
A bright window works, but grow lights or cool
fluorescent tubes are better. Keep seedlings about eight
to 10 centimetres from light source to prevent plants
from becoming too spindly. Plug lights into an automatic
timer set for 16 hours on, eight hours off.
10. Fertilization and Transplanting
seedlings have a set of true leaves along with the first
leaves (cotyledons) start feeding once a week with a
balanced (20-20-20), water-soluble fertilizer at
half-strength, working up to full strength after a few
weeks. At the same time of development you may need to
space or separate the plants into individual pots or
cells. Pick up the seedlings carefully holding the leaf
tips, never the stem. Move them to the new pots and
water well. Keep pots out of direct sun for a few days.
11. Hardening off
Plants grown indoors need hardening off (acclimatized) before they are planted outdoors. After the last frost date, start by setting them outside in a shady, sheltered spot, initially for half a day, then gradually leaving them out all day. Progressively move them into sunnier and windier areas to acclimatize to garden conditions.