Seed Starting Options – Indoors or Outdoors

The snow is still laying around on the ground and many gardeners – like me- have had enough of it. We are waiting and waiting for it to be time to plant our seeds. I have arranged and re-arranged my seed packets by color and by planting time.

It is too early to plant directly into the ground outside, but it is time to sow early seeds into indoor planting trays. If you have never tried it before – have a go – it is easy and you grow lots of flowers to fill up your garden and to share with friends.

I collected my seed packets and sorted them for when and how they needed sowing – notice there is still snow on the ground outside

Outdoor Seed Planting – Cool-Season Annuals and Warm-Season Annuals

First – read the backs of the seed packets and find out whether it is suggested that you plant the seeds inside or outside. Some seeds are best planted straight outside into the soil. These can be divided into two groups – cool-season annuals and warm-season annuals.

Calendula Ivory Princess – seed packet – this is a cool-season annual – it can be planted inside 4-6 weeks before last frost or directly outside about St. Patricks Day in the Mid-Atlantic Area. Adjust these timings later in the North and earlier in the South. In other countries my guide is that I wait for the forsythia to come into bloom and sow them outside then.

Cool-season annuals are ones that can take some cold weather. These tough seeds can be planted directly into the soil as soon as the snow is gone and the soil is visible. In our Zone 6-7 climate we plant these around St. Patrick’s Day – 17th March. But we have to play it by ear – some years earlier by a week and others a week later. We like to plant sweet peas both outside and inside to make sure that we have some of these delightfully scented flowers. Another cool-season favorite is Calendula (pot marigold)

Sweet pea seed packets – I love the fragrant flowers
Deep seed starting modules are great for seeds that need lots of root space like sweet peas. Note that the black seed-sowing pots have holes and the bottom light-colored tray has no holes – but is not permanently filled with water

Warm-season annuals like this gorgeous dark-flowered sunflower that has large seeds that are easy to plant directly in the soil, where you want them to bloom, after the snow has melted, and the soil has warmed up to about 60 degrees F.

Dark flowered sunflower

Seed Planting Inside in Early Spring

Gather your seed-sowing supplies before you start

Some flowers need to be planted inside in trays of potting soil because they take a long time to develop. Gather together your supplies. You will need pots (you can recycle yoghurt pots and other vessels as long as you make a hole or two in the bottom), seeds, seed starting potting soil, small-sized grit (We use poultry or chicken grit – to increase drainage) labels, and some overhead lights. Some people also like to use a heating mat under the seedlings. Follow the directions as to the depth of seed planting in the soil. Some seeds are sown on the surface of the soil, while others need a light covering of soil or small-scaled grit.

Paper-based seed starting trays are great because the whole cell can be planted into the garden without disturbing the plant roots
Seeds may be started inside before the last frost - so that they can grow into seedlings and be planted outside.
Nora Barlow Columbine seed packet – gorgeous flowers – sow 10-12 weeks before your last frost

Columbines are easy to grow from seed. They are sown 10-12 weeks before your last frost date. They take a long time to grow so they are some of the earliest ones to be planted. Once the baby seedlings have grown and have true leaves that look like the adult plant they will be planted outside once the weather has warmed up.

A couple of other ones that we start early (about 6-8 weeks before last frost) are Cerinthe (Honeywort) and Gomphrena. Scabiosa and Amaranthus are sown 4-6 weeks before your last frost date.

Cerinthe is a fabulous cool-season annauls that is favored as a bee plant – Sow 4-6 weeks before last frost
Globe Amaranth – seed packet – a great cut flower – sow 6-8 weeks before last frost
Black Knight Scabious should be started about 6-8 weeks before last frost
Red-leaved amaranthus – sow this dramatic plant 4-6 weeks before last frost or sprinkle them outside on bare soil in spring

10 Key Things to Remember When Sowing Seeds Inside

  1. Sow seeds at the correct time before the last frost
  2. Find out whether the seeds should be planted inside or outside
  3. Plant the seeds at the correct depth
  4. Water the potting soil by filling the underneath tray with water then let the soil drain out
  5. Keep soil moist but not wet
  6. Keep the seeds and potting mix warm while germinating (with a few exceptions)
  7. As soon as the seeds germinate provide light – use LED lights close down to seedlings
  8. Raise up the lights as the seedlings grow
  9. Take the seedlings off the heat mats and keep lights on about 12-14 hours a day
  10. Gradually acclimatize the seedlings to the varied weather outside – then plant in soil

Bye for now Gardening Friends – Enjoy your seed sowing – Jenny Rose Carey

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