Germinating Annual And Vegetable Seeds

It’s really simple if you keep the seed warm and well lit. Here’s how…

Doug Green
Oct 31 · 4 min read

First Step

It’s simple. Sprinkle the seeds over the top of the pot.
This is the first time you can make a small mistake so do this task carefully.

Space the seeds out. Do not lump them into a single area of your soil area.
Try to leave at least one half inch between each seed.

Now I know the seed package has three gazillion seeds and you can only fit 25 seeds into a pot but don’t let temptation override your common sense.

If you overseed, the seedlings will not grow properly. It is much better to plant several pots than oversow.

Excess seed will likely store for another year if it is kept dry and cool so they don’t have to be used up this year.

Overcrowding seedlings leads to disease and weak spindly plants that are not much good in the garden.

I note that with excess seeds, there is no reason why the smaller gardeners among us can not be given their own pot for seed starting.

Marigolds or bean seeds make the best and easiest plant for small children as they are easy, fast and fairly tolerant of over-loving.

Photo by Kill Joy on Unsplash

Once sown, seeds like uniform moisture.

Only use lukewarm water — you’ll be amazed at how fast seeds germinate when you use warm water compared to cold water. (Same temperature as a baby’s bottle works well and yes, you can test it on your wrist.)


While there are a few exceptions to this, gardeners can lightly cover most seedlings to create pockets of moisture around their seeds.

Lightly cover does not mean deeply bury.

While many garden seeds such as peas and corn can grow through one half inch of soil, if a small geranium or petunia seed is planted that deeply, the gardener might just as well put a grave marker on the seed pot rather than an identification tag.

With the exception of the seeds such as pansies that demand full darkness for germination, I cover my seeds so that they are just hidden, with no more coverage than necessary and certainly no more than the width of the seed.

Uniform Moisture

All I want to do is ensure a uniform moisture level around the seed for uniform seed starting and soil surrounding the seed will reduce drying air currents.

Make sure the soilless mix you’re using is fine (no lumps in the seed covering soil) and just sprinkle it over the seed.

Vermiculite is also an excellent covering

Pansies and other “dark” germinators that demand darkness for germination get covered slightly deeper to restrict light levels or are covered with black plastic for 7–10 days to induce germination. There are very few of these in the home garden so barely cover the seed to hold the moisture and not give it “dark” conditions.

Plant Markers

Once covered, I stick a plant marker into the pot to tell me what’s in there. The older I get, the more plants I grow, the more determined I am to label every seed starting pot.

An unlabelled pot is a forgotten pot.

Cheap labels can be obtained by cutting up tall margarine or yogurt tubs and using indelible magic markers or soft pencils for writing.

Using water soluble markers is only asking for disappointment as they will fade away in sunlight or melt away if wet.

A soft-lead pencil makes a long-lasting impression on wood or plastic.

Soil Heat

Now that the seed is sown, covered and marked, we have to ensure adequate soil heat.

Unlike perennials that often germinate in cool soil temperatures, annuals and vegetables want a warm soil temperature to ensure germination. Soil temperatures of 72F are common in the trade for obtaining good results.

Note that soil temperatures are usually 10 degrees cooler than air temperatures. While sunny windowsills will warm up nicely during the day, they are much cooler at night.

Find a good warm place for the seeds until they germinate.

Some gardeners use the top of an old, yet working fridge to take advantage of the heat generated by the compressor. Check whether the top of your fridge is warm because frankly, I believe this to be a non-starter given modern energy-efficient refrigerators.

I use a small heat mat that provides an even constant temperature for my seed starting efforts. Or, I also use a 100 watt light bulb suspended in an aquarium (aquarium top is covered with clear plastic to hold in the heat)

Immediately After Germination

Once the seeds have begun germination, they can and should be moved to a cooler spot —mid 60’s F — and given as much sunlight as possible.

This light is critical for the development of the plant and must be provided either by an unimpeded south facing window or a combination of window and grow lights.

Plants without adequate light grow tall and spindly as they stretch out in search of this light they require for energy and growth.

Doug’s Propagation Chamber

propagation chamber
propagation chamber
propagation chamber

I use this for taking cuttings and sowing seeds. Works like a charm.

  • This is a 25-gallon aquarium,


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Doug Greens Garden

A practical organic gardening resource helping you have a better garden

Doug Green

Written by

Former nurseryman, now writer and curious about what’s over the next hill and how to get there in either my Triumph Spitfire or sailboat.

Doug Greens Garden

A practical organic gardening resource helping you have a better garden

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