Let’s troubleshoot why your you had poor germination with you seeds. There are unfortunately many reasons why your seeds did not sprout. Here is 8 of the most common reasons and fairly easy fixes.
So you took the time to plant a bunch of seeds, saw visions of your abundant harvest, patiently waited day after, day after, day…. and then nothing happened.
Especially after waiting all winter to start those first seeds in the spring, when they don’t sprout, it’s so disappointing. It can make you feel like a failure and the season has just barely begun.
Now, some seeds won’t germinate. It’s good to understand this now. This is just their nature but there are several things we can do to increase the odds. This is why planting you always add a few extra seeds in each pot. Typically germination of new seeds should be 75% or higher.
8 Reasons Why Your Had Poor Germination:
#1 Old Seeds
Have you had that seed packet forever and a day? Seeds do get old and lose their potential to germinate after roughly 2-5 years. ie. the % that will germinate goes down. A new seed package for most seeds will give you 75% germination rate or higher. Now there are definitely exceptions like Lavender or Strawberry from seed where you are more likely to get a 20-30% success rate (and why they are my arch nemesis… that’s a whole other blog post).
#2 Seeds not stored correctly
Seeds are best kept in a cool dark place free from moisture ie. a closet (mine are in my linen closet on the floor 🤷♀️). If we think about it, seeds need heat, light and moisture to grow. So if you want to keep them from trying to grow and getting spoiled, keep them in an environment that is the opposite.
#3 Too much soil covering the seeds
Pay attention to what the seed packet says so those little seeds don’t lose all their juice before they can poke up and say hello. Those super teeny tiny seeds can only be covered with the tiniest amount of soil. In some cases not even covering the seed and just pressing it into the soil is best. (like Lavender or savory). Seeds only have so much energy within them to send up that first shoot up. Bury it too deep and it won’t make it.
#4 Need Heat To Germinate Not Sunlight
Most seeds need heat to germinate. It does not mean that you won’t get germinate if it is cloudy but it will take longer and can mean a lower % that will germinate. Starting seeds in a cold basement generally is not recommended without supplemental heat. The same goes for starting outdoors when the temps are cooler. Covering the soil with a row cover fabric for insulation is a great way to boost the soil temps to reduce poor gemination rates.
Good ways to get heat for germination indoors:
- The heat from grow lights (led’s do not generate heat)
- Window sills – while the sun is shining.
- Top of fridge or other warm appliance
- Invest in a seed starting heat mat. This is the one that use. It has a thermometer as well which is great to boost success for seeds that need a very specific temperature to germinate.
#5 Seeds Did Not Have Ideal Temp To Germinate
Each plant has an ideal temp to germinate. Deviate from that and the % will go down for germination rate. You don’t always need a heat mat to facilitate this but definitely get yourself a thermometer to test different areas of your house to find out what the ambient day and night time temps are so you can use that.
You can even find thermometers that can can tell you what you max and min temps are in a day. This takes a lot of the guesswork out of understanding what went wrong. If you see that you are quite often outside the ideal germination temp for those seeds and had poor germination, vs more successful germination at ideal temps, you can start to connect the dots and gain better understanding of the seed germination process.
#6 Seeds Need Light To Germinate
There are few seeds that do prefer bright light to heat to germinate such as lettuce. Sometimes some research helps ahead of time. (add it to your garden journal)
#7 Too Much Moisture & Seeds Rotted
This happens to even the best of us. The best tip I can give to reduce the chances is to pre-moisten your soil before seeding starting. I use a bucket to add the soil and water and stir it well until it is evenly moist (wet enough that when you squeeze it a water droplet almost comes out but not quite) to ensure even moisture. After I place the seeds in the soil I give the tiniest extra dribble to the top of the soil.
Cover with some sort of lid that will keep the moisture in. It is better to keep the moisture in during germination than trying to keep adding the correct amount.
There is a good chance, with a lid, that your seeds will germination without needing to add more water for plants that tend to germinate faster (5-14 days).
#8 Not Enough Consistent Moisture
(see pre-moisten tip above)
The flip side to #7. Inconsistent watering is probably the #1 reason that poor germination occurs. It is also the hardest to get right sometimes.
Not letting your soil dry out is also very important. Keep your seed starting tray covered to keep it from drying out super quick. Placement of your tray is also important. If you have it too close to an air vent it will dry out too quickly. The sun can dry out the little tiny pots pretty quick as well. Always keep a close eye on what’s happening.
Keep A Garden Journal To Prevent Poor Seed Germination
- Mark down the date you started each plant. We always think our memories are better than they are. This will help you too clearly know how long it has been and if you should start over again or keep waiting.
- I recommend also adding a note on the typical germination time for each seed. This you can find by googling.
If you are part of my Complete Gardening Season Course bundle you will have access to my super detailed seed starting spreadsheet with everything you need to know from time to germinate to temperatures and any special extra tips required to boost your success!
Not a part of the Complete Gardening Season Course bundle? Now is the time to join by clicking here. Learn online on-demand all year long. Learn over the winter and then have it to refer back to all summer long with concise videos you can take right out in the garden!
Learn my full process for seed starting my click this link. Learn about ideal dirt, containers and how to choose your seeds.