Tomato and pepper seed start time

Fri. Apr. 6, 2018

Click below to listen to my 2 min. Garden Bite radio show:  Tomato and pepper seed start time

Nothing’s better than a homegrown tomato.  You can make that experience even better by starting your own from seed.  The best barometer for planting tomatoes and peppers outside is when the soil temperature is 60 to 70 degrees.  Usually that’s Memorial weekend in zone 4 and a week or so later in zone 3.   Planting early usually means stunted growth.  I’m going to start some seeds within the next week or so.  It’s still darn cold in the Upper Midwest!

If you start seeds too early indoors you run the risk of them becoming leggy which can translate to weaker plants.

a great slicing tomato! Big Boy

Choosing the type of tomatoes you want is part of the fun.  Oh so many choices!  Romas and slicers, cherries and grape, heirlooms and hybrids.


Then there are peppers!  Bell and hot, banana and Italian.  Again, it depends on what you use them for.  I happen to love the Italian pepper ‘Godfather’.  They’re prolific producers and very tasty.  They grill up well too.

Pepper – Flavorburst 8-16-15


Now how to start seeds.  Use a sterile starting mix.  I like using the peat pots rather than other containers, they’re simple, ready to roll and you can plant the whole thing in the ground once it’s time.  Plant your seeds according to directions on the packet.  I have a heating mat that keeps a steady 70 degrees.  Place your plants in a tray under a shoplight.

Once the seeds sprout, keep the light at 6 inches above the plants, leave it on for 16 hours a day.  I use a fan to gently blow across the plants for about an hour a day.  A pulley system works well to move the light as the plants grow.

pepper seedlings under shoplight with heat mat


I would not put the peat pots directly on the mat.  Place them in a plastic container on the mat.  Keep the seeds moist while germinating, a spray bottle to water the soil surface without blowing out the soil is useful.  There’s no need to fertilize until the plants have several true leaves.  Then use a weak solution of all purpose fertilizer once a weak.  Less is better.

Keep your seeds and seedlings MOIST, not wet.  You’re looking for your plants to be robust, stocky.  If they get leggy, they’re not as healthy.  Tomatoes can be planted deep and in fact, should be.  Roots will form all along any stem that’s in soil.

There are certainly other ways to start seeds indoors.  Here’s a great article from the University of MN Extension.