By starting seeds indoors you can often extend your growing season by up to ten weeks. This can be very beneficial for plants that have a longer “days to maturity" time frame. You can even start some of the newer hybrid varieties with shorter "days to maturity” time frames indoors and then sow some directly into the garden so you can have a harvest of produce early and over an extended period of time throughout the summer months.
When starting seeds indoors you want to determine the last frost date in your area. This is usually June 1st in our area. This may seem late because sometimes in May we have hot summer days but June 1st is the average last frost date for this area as we can still get frost at night after a warm day. Count back the desired time from this date to determine the time to start your seeds indoors.
Don't start your plants too early because the temperatures indoors, can be a little warm and the light conditions a little low and end up producing weak, pale green and spindly seedlings. Plants growing indoors prefer temperatures between 10-16 Celsius instead of the 20-22 Celsius that a home temperature is usually set at. The ideal place would be a south-facing three-season room, but we do not all have those attached to our homes. You may have to sacrifice a cooler place in order to make a place for the trays with adequate light, like a south-facing window.
In areas where you are short of light, fluorescent lights can be hung above the planting trays. Use a forty watt, double light fixture with two lights for every four trays of plants that you have. Suspend at a height so that all trays get even exposure but never closer than 25 cm so there is room for the plants to grow. If you have a grow light system you can even grow plants in your basement or heated garage and not have to move the trays around to chase the light exposure in the house, throughout the day.
Gather all of your potting trays or pots together and make sure that if they are either new or are thoroughly cleaned and then rinsed in a bleach solution to ensure that any traces of moulds and bacteria are gone. You can also use peat pellets that are condensed disks of peat that expand into a pot once hydrated with water. One seed per peat pot is ideal and makes for easy out planting. It is important to choose a good potting mix for starting your seeds, a soil-less mix is most desirable. Never use soil from your garden for starting seeds. This soil will start to compact tightly soon after planting, stunting the growth of the seedling, along with the fact that this soil will be filled with weed seeds, moulds and bacteria that will flourish in the growing conditions of the house.
Fill your trays, pots or planting containers three-quarters full of potting mix, sow the seeds on the surface and then cover with a light sprinkling of soil. Water the soil so it is very moist but not water-logged. Water slowly, so as not to wash all the seeds out from under the cover of soil. To trap the heat and moisture, place the clear plastic lids on the planting trays and containers, making sure you have a tight seal. If you do not have a clear cover for your container, place it inside a clear plastic bag of choice and seal tightly. Keep the trays warm until the seeds germinate using some of the tips from last week. Once the seedlings reach the top of the plastic cover remove and treat like any houseplant until time to put the seedlings outside. Do not let the soil dry out when the seeds are germinating, even if you have to remove the cover to water. Make sure once you remove the cover permanently you do not let the seedlings dry out but also do not waterlog them.
Starting seeds indoors helps to chase away the winter blues and you to get a jump start on the gardening season. It is also an economical way to fill your garden with plants as well as try new plants species.