Fascination of Plants Day

Plant Cultivation Guidelines

>> Download Guideline <<

The seeds will be sent to you in little paper bags by post. We will also enclose a plastic chip you can use as the size reference when you take pictures of plants (see point 8).


You can start at the end of April (or somewhat earlier if you live in a warm country, somewhat later if you live in a cold country, there should be no severe night frost).

  • Take two garden pots as similar as possible. Put potting soil or other soil in both pots, make the surface flat and wet the soil with water just before sowing.

  • Sow all seeds from a paper bag in one pot, and all seeds from another paper bag in the second pot. Be careful, thale cress seeds are very, very tiny! Baby plants (“seedlings”) won’t be able to grow out of the soil if you bury the seeds in the soil. Just scatter the seeds over the soil, like these seeds naturally fall to the ground.

  • Write down the date of sowing (Date 1).


Place both pots somewhere inside in the light, for example in a greenhouse or by the window in a room, until some seeds have germinated.

  • Keep the soil always wet during germination because seeds and seedlings are very sensitive to drying! Do not put the pots in full sunlight or near the heating. You can also put a plastic bag over the pots during the first days to avoid drying.

  • When you give water, do it gently so seeds and seedlings won’t be flooded and drowned.


As soon as you can see the first two green leaves, take tweezers and carefully remove (“thin out”) all seedlings except for four or five. It is best if the plants in both pots are of similar size.

The first two leaves
Thale cress belongs to the group of plants called ‘dicotyledons’ which first grow two baby leaves (“cotyledons”). They were hidden inside the very small seed! Grasses do things differently and start with only one leaf…


After that, place one of the pots outside in a garden or on a balcony.

  • If you do it in a garden, you can dig a small hole to place the pot in the ground. This way the temperature in the pot will be comparable with the temperature in the ground where plants normally grow their roots.

  • The other pot is kept inside in a greenhouse or by the window. If you have access to a growth chamber (at universities or plant research institutes), you can also put the “inside” pot there.

  • Write down the date of separating the “inside” and “outside” pots (Date 2).


Water the plants if the soil looks dry, but not too much.

  • If there is still frost expected during the night, it might be good to cover the pot (for example, put a plastic box over it), as soil frost may otherwise kill the plants. Do not forget to remove the cover the next morning!


After about a week from Date 2, check the number of plants in each pot. Did seedlings in the “outside” pot survive? (We hope so!) Then reduce the number of plants to only one in each pot. Do so by removing all leaves of the other plants. You don’t have to dig the soil to remove their roots since this may upset the plant that should remain in the pot.


After four weeks from Date 2 you can collect the two pots.

  • Place a paper with a written sign marked “I” (from inside) next to the pot from inside, and with an “O” (from “outside”) next to the pot from outside. Place the plastic chip as size reference next to the plant (don’t cover the plant with the chip!) and take a picture with your smartphone or other digital camera.


Instructions of how to send us your pictures.

 After you have taken the final picture of the inside and outside plant, including the chip, could you please send them as attachments to "everyplantmatters@fz-juelich.de". We will process them further and publish them on the website.

On this website, we would like to provide the following information along with your pictures:
1. Your name (only if you like, otherwise leave open)
2. The city where you did the experiment
3. The country where you did the experiment
4. GPS location (latitude and longitude. You can use your smartphone or google your city and “coordinates”)
5. Date of sowing (like 27-04-2017)
6. Date when the outside plant was placed outside
7. Date when the pictures were taken
8. Remarks, like whether your inside plant was grown in the living room, glasshouse or growth chamber, and whether your outside plant was from on the balcony or in the garden).

It would be great if you could use the attached Excel file to supply that information, but if you do not have Excel, no worries, you can also provide the info as text in your email.

Best wishes,

Shizue & Hendrik

>> Download Guideline <<


Shizue & Hendrik