Goal

This project will cover aspects of the growth of ragwort and its nature by planting seeds and by growing a containerised plant that will later be used in biological control projects.  The goal is to understand the stages and needs of the ragwort plant, together with ragwort's evolved survival strategies.

Equipment and materials

1. 10 lt plastic plant pot and watering saucer.
2. Three 3 inch plastic pots.
3. 20 lt of Multi Purpose Compost.
4. One ragwort rosette stage plant (ca 1cm crown or greater).
5. 1m of brightly coloured string.
6. 500ml of small gravel or chippings.
7. Two 50ml screw top clear plastic pots.
8. Ragwort seeds.
9. Washing-up liquid
10. Clipseal plastic bags or polybags with a tie wire.
11. Some cress seeds.

Safety equipment

• Nitrile gloves or thick rubber gloves for use when handling ragwort.

Part 1 - Germinating and growing ragwort seeds:-

Ragwort relies on a large reserve of seed in the ground in order to escape occasional plagues of Cinnabar.  The seed must last a long time in the soil and must not all germinate when it first touches the ground as many plant seeds do. To make sure that the seeds do not all germinate as soon as they touch the ground, ragwort has evolved several hurdles that the seed must ‘jump’ before it can  germinate.  These are:-

• Seed is held in the seed head until the following year when stormy Spring weather blows it away.
• The seed must be washed several times in order to remove growth inhibiting chemicals.
• The moist seed must be exposed to sunlight for several days in order to germinate.

To show these controls at work we will set up four trials:-

Trial 1  --  ‘WARM and DARK’

1. Fill the 3 inch pot with compost and firm the compost down. 
2. Water the compost thoroughly until water runs from the bottom of the pot. 
3. Let excess water drain out of the pot for 2 minutes.
4. Sprinkle a quarter of your ragwort seeds onto the top of the wet compost.
5. Cover the seeds with about 5mm of compost.
6. Place the pot into a clipseal bag and seal the bag.
7. Place the bag and pot into a dark cupboard in a warm room.
8. Inspect the pot every week to see if any seeds have germinated.
9. Keep a germination log for this pot under the title of ‘WARM and DARK’.
10. Repeat this trial with cress seeds instead of ragwort seeds.

Trial 2  --  ‘LIGHT not WASHED’

1. Put 5ml of water into one of the 50ml screw top clear plastic pots.
2. Sprinkle a quarter of the seeds into the pot.
3. Screw on the lid and gently swirl the pot to mix the seeds with the water.
4. Mark the pot ‘LIGHT not WASHED’.
5. Stand the pot in a window in full sunlight.
6. Inspect the pot every week to see if any of the seeds have germinated.
7. Keep a germination log for this pot under the title of ‘LIGHT not WASHED’.

Note that the water becomes coloured.

Trial 3  --  ‘LIGHT and WASHED

1. Make some ‘wet’ water by putting one drop of washing-up liquid into 1lt of tap water.
2. Put 40ml of ‘wet’ water into the remaining 50ml screw top pot.
3. Sprinkle a quarter of the ragwort seeds into the pot.
4. Screw on the lid and swirl to mix the seeds and water.
5. Mark the pot ‘LIGHT and WASHED’ and place the pot in a window in full light.
6. Every day, open the pot and carefully pour off the water, keeping the seeds in the pot.
7. Replace the water with 40ml of fresh ‘wet’ water, mix, lid and return to the light position.
8. Continue washing the seeds for one week, note that the water stops being coloured.
9. After one week, drain off the water and top the pot up with just 10ml of fresh water.
10. Leave the pot in full light and do not screw the cap on tightly.
11. Keep a germination log for this pot under the title ‘LIGHT and WASHED.

Trial 4  --  ‘POTTED, LIGHT and WASHED’

1. Fill the remaining 3 inch pot with compost and firm down the compost.
2. Water the compost thoroughly using ‘wet’ water until the water runs from the bottom.
3. Let the excess water drain for 2 mins.
4. Sprinkle the final quarter of the ragwort seeds onto the top of the wet compost.
5. DO NOT COVER THE SEEDS.
6. Note: If your compost is very light, it might float up and cover the seeds when you water them.  To prevent this, put a 5mm layer of sand onto the top of the compost before you put on the seeds.  The dense sand will keep the compost down and will ensure that the seeds stay on the surface.
7. Place the pot into a clipseal bag and seal the bag.
8. Place the bag in a light window.
9. Mark the bag ‘POTTED, LIGHT and WASHED’.
10. Every day gently pour 40ml of wet water onto the seeds on the top of the pot, being careful not to disturb the compost - this could bury the seeds.
11. Let the water drain out of the pot for 2 mins and then return the pot to the bag.
12. After two weeks stop watering the seeds.
13. Keep a germination log for this pot under the title ‘POTTED, LIGHT and WASHED’.
14. When seedlings germinate, note the shape of the leaves and compare them with the seedling images in the Ragwort section of this site.

Q1 Does ragwort germinate like cress?
Q2 Does ragwort germinate in the dark?
Q3 Does ragwort have to be thoroughly washed before it can germinate?
Q4 What evolutionary advantages does this behavior give ragwort?

Part 2 - Growing a Flowering ragwort Plant:-

1. Half fill the 10lt pot with compost, firming the compost well.
2. Build a cone of compost in the middle of the pot reaching up to the rim of the pot.
3. Place the ragwort rosette plant onto the top of the cone so that the roots spread out down the sides of the cone. WEAR GLOVES WHEN HANDLING RAGWORT.
4. Select a thick root and tie the coloured string loosely around the root about 2cm from the crown of the plant.  Put the ends of the string onto the plants leaves.
5. Fill the pot with compost, and firm down gently. The compost should just come up to the base of the ragwort leaves.
6. Cover the surface of the compost with gravel chippings.
7. Water the compost thoroughly until the water runs out of the bottom of the pot.
8. Allow the pot to drain, then stand the pot in its watering saucer for 5 minutes.
9. Make sure that the watering saucer is about half full and stand the pot and saucer in full light in a sunny window or greenhouse.
10. Leave the coloured string over the edge of the pot.  Later the string will be used to locate the thick root it is tied around in order to carry out a root experiment.
11. Water the pot every day and make sure that the saucer is left about half full.
12. As the rosette plant grows, note the shape of the leaves and compare them with the shape of the seedling leaves. Note how the leaves press down onto the ground.  Note how the leaves make a mound shape like a rosette.
13. After about 2 weeks , remove the chippings and the compost from around the coloured string to locate the thick root. Using scissors, cut out a section of the root about 1cm long. remove it and fill the hole back in with compost.
14. Once the plant is ready, it will start to ‘bolt’. Notice how the centre of the plant starts to shoot up - this is ‘bolting’.
15. The plant will soon be ready to flower and seed, observe the changes it goes through and the shapes and colours of the leaves and stems.
16. Gently brush the leaves with a stick and notice the smell which gave ragwort one of its old names ‘Stinking Willy’.

Q1 Research other names for ragwort - how did it get those names?
Q2 Which parts of the plant are poisonous?
Q3 How could you get poisoned by ragwort?
Q4 What were the most common ways that people were killed by ragwort?
Q5 What advantages are there to the rosette shape?
Q6 What advantages are there to the plant’s smell?
Q7 What advantages are there to being poisonous?
Q8 Does ragwort only grow from seeds?
Q9 How much ragwort is there around your school or town?
Q10  What stages of growth are the plants at?

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