Starting Seeds Indoors

Seeding indoors not only saves you money but is an easy and enjoyable way to enjoy just a bit of spring during long winter months. Though seeds are easy to grow, some first-time ‘seeders’ may experience less than perfect results. So, before you get growing indoors, here are some helpful tips.

When to Start

Most plants should be seeded approximately 6-8 weeks before planting out. In our area most annual seeds will be started from April 1st to April 15th, so plants are ready to place outside May long weekend. There are exceptions; Petunias, Seed Geraniums, Begonias (an extra couple weeks earlier produces bigger plants). Perennial seed is best started 10-12 weeks prior to planting out. For a specific timing schedule for starting seeds indoors check out the Almanac Planting Calendar

How to Start

Step One

Seeds can be started in many containers, however for most young seedlings cell packs are ideal. The cells are the optimal size for many plants to grow in until planting outdoors (crops requiring longer grow times such as 8-12 weeks may require a transplant). These cell trays can be filled with seedling mix such as PROMIX Seed Starter and placed into a seed tray to collect any moisture runoff when watering.

Jiffy Seed Pellets are also a great choice. These peat pellets are simply soaked in water, after which they swell up into a miniature pot that the seed can be placed in. The roots grow into the peat medium just as they would in soil.

Though pellets are great for lessening ’transplant shock’ on seedlings, roots may outgrow the pellets, requiring a transplant into a larger pot (4”) with soil.

Step Two

If using cell trays, fill them with moistened soil. Place a seed in each cell (or in the top of each peat pellet). If you get too many in one cell, don’t worry, you can thin it out later. Sprinkle a thin layer of soil over the seeds. If planting in pellets, simply press seed into the top center of the pellet pot.

Step Three

Use a mister bottle or watering can with very fine holes to water the soil in. In the following weeks it is recommended that when watering, you use a strong chamomile tea solution to water seeds/seedlings. This will prevent the onset of Damping Off, a damaging fungus that can kill seedlings. To make this solution, add 4 tea bags to a teapot full of boiling water, let steep overnight.

Step Four

Place a clear dome over the tray to keep humidity in. It’s beneficial to place the seed tray over a seedling heat mat (these can be purchased at Greenland) to help promote germination. Germination times will vary with different plants, but on average you should see signs of growth within 7-10 days.

Step Five

Once you see signs of growth, it is very important to provide the seedlings with sufficient light. A brightly lit window will suffice, but for the best light source use a full spectrum light. Our Jump Start light kit will light between 3-6 flats of seeds and is energy efficient and portable; simply plug in and grow.

Step Six

Once the seeds have germinated you can remove the humidity dome. Continue to check daily for water, and use a watering can with a fine nozzle or mister bottle.

Step Seven

In May, when weather warms, you can place the seed trays outside to acclimatize them to our weather. As long as the daytime temperature is above 4ºC, the seedlings can be placed outside (if evening temperatures are still cool, simply bring them in for the night).

Step Eight

Once seedlings have acclimatized (within a week of being outside daily) you can transplant them into the garden. Ensure soil is prepared; any hard packed or clay soil should be amended with compost or Sea Soil to improve drainage and provide nutrition. Try to transplant them out on a cooler, cloudy day as opposed to a hot, sunny day. If the day is to be warm and sunny, try to transplant quite early in the morning, or late in the day.

New to Starting Seeds indoors?

No problem – our knowledgeable staff are on hand to help with lots of tips to get you started watch our Indoor Seeding – Starting for Spring Success video.