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INDOOR SEED STARTING 101 - Sowing the Seed (Part 3)

In this, the last of a 3-part series, I will walk you through the steps of all things seed, seedling and transplant related. Keeping true to my belief of keeping it simple, I have intentionally mentioned the most important steps to ensure success but have not bogged the reader down with too much detail. Remember, gardening is a journey that is meant to be enjoyed.


Knowing when to start seeds indoors is important and also confusing. Because we are striving for the healthiest, optimally-sized transplant for setting out in our gardens, timing is rather crucial. The first thing you must determine is your areas Last Frost Date (LFD). Once this is known, use the chart below to determine how many weeks in advance each particular crop will need (in terms of weeks) from seed to set out in the garden.

Indoor Seed Sowing Guide

Thanks to the Farmer's Almanac, determining your LFD is as easy as clicking on this link. Armed with this date, go find a calendar, and using the INDOOR SOWING GUIDE, (pictured) you will now know exactly how many weeks before your LFD to sow the most common garden crops.

IMPORTANT: As much as you may want to, do not start seeds earlier than recommended, as you will most certainly end up with straggly seedlings that will never recover once they are set out in the garden. It is, however, okay to start seeds later than recommended by 2-3 weeks as they will eventually catch up in the garden.


Over the years, I have developed the habit of microwaving ALL of my commercial seed starting mix before I use it in the house. Why? Because aphid larvae just love to hitchhike along in it. Is this step necessary? Absolutely not. It's just what I do.

In a glass bowl add soil and water to moisten. Microwave for 4 minutes.

Fill a glass bowl (my preference for ease of cleaning afterwards) with as much soil as you feel you will need. Add enough water to moisten to the consistency of a damp sponge. Less is more, as you can always add to. Microwave for 4 minutes. Remove the bowl and stir thoroughly. It will cool down rather quickly. Any remaining soil can be stored for later use.


Whatever container/pot/tray you decide to use, keep in mind that you do not need to overfill it and it does NOT need drainage holes. These are temporary homes, so there is no sense in wasting soil. An average of a couple of inches is just fine. My preferred method of sowing is called the Dense Planting Method. I was introduced to this method by the author of the video, Craig LeHoullier many years ago and have used it ever since. (BTW, I had the pleasure of meeting Craig and he really is as normal as he seems in his video(s).) This method is truly a space saver.


An often overlooked topic is how deep seed(s) should be planted? In most cases, that information will be printed on the back of the seed pack. But, what if it isn't?

A good rule of thumb is to use the "3 times the width of a single seed". For example, corn would be planted a full inch deep. While lettuce, which is very thin, would be planted nearly on the surface, with just a dusting of soil over the seed. Note, that with larger seeds (corn, squash, beans, peas, etc. planting a bit deeper is better than too shallow).


The biggest lie we will ever tell ourselves is "I'll remember what that is." No. No, we won't.

There are many different ways to label your containers and over time you will find a system that works best for you. I usually cut up plastic tags into very thin strips and use a PENCIL on the dull side of the tag to mark my pots/rows.

I have also used blue painters tape (writing with a Sharpie), on the outside of the container with great success, as well. NOTE: If you have small children, you should consider this system because no one likes to see a grown person ugly cry.

Popsicle sticks are popular and can be found in craft sections almost everywhere. One option that is often overlooked is used mini-blinds. They are usually easy to find in thrift stores. Cut off all the cording and cut the remaining slats into manageable pieces - you now have enough material for years worth of labels. Remember that you want to write on the dull side and use a No.2 pencil!!

Note the clear dome tipped up behind the tray.


Place your pots/trays complete with fitted domes ( or plastic wrap) on top of your heat source. It's not necessary that they be under lights at this point. However, once you see seedlings emerge you must put them under light.

Lights need to be on for a minimum of 12 hours (I prefer 16 hours) and off the balance of a 24 hour period (this is where a timer comes in handy). MAKE SURE THAT LIGHTS ARE KEPT 2-4 INCHES ABOVE SEEDLINGS AT ALL TIMES.

Once all of the seedlings have poked through the soil, it is time to begin to remove the plastic domes. This is a process - especially if your seed starting area is cold. On day one, lift the lid and prop it open about an inch (I use pencils). The next day, prop it open 3-4 inches. By the third day, you can remove the domes completely.


Almost all indoor seed starting failures are due to these three things: leggy seedlings (not enough light) over-watering (soil should never be wetter than a damp sponge) lack of air circulation (no air movement) I can't express how important it is to keep an oscillating fan gently blowing on seedlings for indoor seed starting success. Constant air flow creates tough seedlings with thick stems.


One of the quickest way to kill your seedlings is to over water them. They are far better off on the drier side than the opposite. It's worth mentioning that when you do water, be very mindful of doing so gently, so not to displace the seedlings. I've seen some people use recycled "Honey Bear" plastic bottles. This seems like it would work well on a smaller scale. Nonetheless, you get the idea to be careful.

Seedlings do not need to be fertilized until the first set of true leaves have formed. And then you will only do so at 1/4 strength of manufacturer's direction.


Transplanting can make a lot of people nervous, but you really needn't be. In fact, it may seem counter-intuitive but the smaller the seedling the easier it is and transplant shock/recovery is kept at a minimum. Here is a video of how I do it step by step:

If you have questions or comments, drop them below. Now, go sow some seeds!

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