In the Dutch version of this tip, there is information about the text on Dutch seed package. It contains lot number, production year and best before date, or expiration date.
On the internet there is much info about seed package information “outside the Netherlands”. On that package there is often a “Packed for” year and a “Sell by” date.
A)# Witloof (Chicory) seed, information and test.
A1) Four seed sachets
I bought these 4 packages of chicory seeds in 3 different garden shops.
I identified the packages with a blue pen (1,2,3 or 4). When you click on the narrow photo above, you see the packages screen wide. On each package there is an expiration date or year (“BRUIKBAAR TOT” or “THT”) of 2015, 2016, 2017 or 2018.
A2) Germination test of Chicory
Seeds from each package have been used in the following germination test.
On this photo you see the results of germinating chicory seeds on moist toilet paper. Number 1,2,3,4 at the plastic box indicate the package numbers. At nrs 1 and 2 there is very little germination. Seeds nrs 3 and 4 show 100 % germination.
On this photo you see the results of germinating chicory in moist garden soil. Seeds have been put in small sowing holes and were covered with a thin layer of dry garden soil.
Again there is very little or no germination at seeds nrs 1 and 2. Seeds nrs 3 and 4 show more than 90 % of germination.
Chicory seeds of nrs 1,2,3 and 4, sown in sandy garden soil (in my backyard garden). Seeds were covered with garden soil and little plastic flower pots.
Chicory plants in the garden soil after germination. From left to right chicory seeds of nrs 1,2,3 and 4.
Again there is very little germination at seeds nrs 1 and 2. Seeds nrs 3 and 4 show much germination.
B)# Winter leek
This photo shows 2 rows of winter leek plants in my garden soil. All leek seeds have baan sown in 2 furrows on March 16 (late winter, early spring). In each furrow 3 seeds per 10 centimeters (4 inch). Two different leek varieties.
In the front row only few plants have emerged.
- In the rear row, many seeds have turned into leek plants.
- In the front row only few leek plants have emerged.
- Cause: “older” or “newer” leek seeds.
The leek seeds of the rear, full row had an “expiration date” of 2 years after sowing date”. According to the package, this seed could be used 2 more years. This seed was “less old” , in other words “newer seed“.
The leek seeds of the front, thin row had an “expiration time” of 1 year after the sowing date”. According to the package, this seed could be used only 1 more year. This seed was “older seed“.
This photo shows the same 2 rows of leek plants, a few weeks later. The red white arrow indicates the full row of leeks, grown from “newer seeds”. The black white arrow is at the thin row of leeks, grown from “older seeds”.
Left photo: a 10 liter bucket filled with all leeks from the full row. Right photo: a 10 liter bucket with all leeks from the thin row.
- Expiration data are not always true or real.
- When you doubt about germination power, you better test the leek seeds; lay 10 to 20 seeds in a tray on moist toilet paper or on moist kitchen paper. Put a lid on the tray. Find out how many seeds turn into plants.
Complainting in the shop or at the supplier about bad germinating seeds will not be successfull, I think. The shopkeeper or supplier will mention the “Packed for” year and/or “Sell by” date. Or say that bad germination is due to the bad weather or your garden soil.
Little chance that the supplier or shopkeeper will report that the storage at his company was not good. And that he or she will give or send you new seeds for free.
D)# Germination test (1)
This photo shows the results of a germination test for (from left to right) egg plant, winter carrot, onion and summer carrot (2 brands) on moist toilet paper. Seeds have been germinating for 6 days at about 68 F (20 C).
E)# Germination test (2)
Three seed packages; onions, onions, tomatoes.
With these expiration dates (onions, onions, tomatoes); 2021, 2021, 2018.
Germination test of these seeds in 2018. From left to right; 2 rows of onions, 2 rows of onions, 2 rows of tomatoes.
Conclusion: The “old” tomato seeds (exp 2018) germinate much better than the “new” onion seeds (exp 2021).
My practice; tomato seeds from one package can be used several years after another. But onion seeds germinate bad after 1 or 2 years, so you better buy new onion seeds each year.