Mint Activity of the Week
Got your Free mint pack yet? For all of you making a ‘mintal’ note to start planting your mint seeds – read on! It could save you constantly watering the thirsty little var-mints. It comes to you direct from the brain of a top Plant Science expert from SAPS, also responsible for the content of the Mintformation Wall Chart you get with the seeds.
Growing seeds in film pots
Introduction
Does growing plants indoors take up too much space? Is it a problem knowing how much water to give your seedlings? The SAPS method of growing plants in film pots could be the answer.
A whole range of seed including radish, broccoli, tomato, wheat, sunflower, sugar snap pea, and sensitive plants have all done well grown this way. An added advantage is that when the seedlings are large enough to transplant each seedling can be moved in a plug of soil so that its roots are not disturbed.
What you need
- Black film pots (free from any chemist or camera shop that develops films)
- A sharp nail to make holes in the base of the film pots
- Capillary matting (from a garden centre)
- Peat-free compost
- Fine grade vermiculite (from a garden centre but not essential)
- A plastic box with a lid e.g. a plastic food storage box
- Adhesive tape
Preparation
Make the water reservoir (see photo above): Cut a slit at one end of the lid. Cut out a piece of capillary matting to fit the lid and with a tail that passes through the slit. Fill the box with water and replace the lid.
Prepare the film pots (see illustration to the right): Use a nail to make a hole (about 2mm diameter) in the bottom of the film pot. Cut wicks out of the capillary matting and pull these into the film pots so that the pointed end comes halfway up the inside of the pot. Tape the pots together in bundles of 4 or 5. This makes them more stable when they are on the water reservoir.
Make the soil mix: Add a small amount of vermiculite to the peat-free compost (3:1 compost: vermiculite). It is not essential to add vermiculite but it helps to retain moisture.
Add enough water to just make the mixture moist and remove any large lumps.
Planting the seeds
Fill the film pot nearly to the top with the soil mix, gently tapping the pot while you do this to help the soil mix settle. Add water drop by drop to the film pot until the wicks just start to drip.
Add a few seeds (2 or 3 if they are large enough to handle or a very small pinch for tiny seeds).
Just cover with soil unless the seed packet suggest otherwise and place the pots on the water box. Place the water box with its film pots in a warm light place but not in direct sunlight. A light bank is ideal (see the SAPS website).
Caring for the seedlings
At first you will need to add 3-4 drops of water to the pots each day. Once the seedlings appear you can stop as the soil will draw enough water from the reservoir to allow them to go on growing. All you need to do now is check the reservoir from time to time to check that the capillary matting is still in contact with the water.
When the first true leaves begin to appear remove all the seedlings except the strongest one which is left to go on growing. Transplant the seedlings to larger pots when they are big enough to handle.
See the SAPS website www.saps.org.uk for more information, other interesting ways of growing plants and lots of ideas for plant investigations.
Just a very quick thank you to all the Planet Science Newsletter readers that volunteered themselves to provide children’s judging panels for this prize. The 25 Planet Science groups have been chosen and are literally all over the UK. Here they are as a long list:
Where can you explore deepest space, find out how doctors perform life-saving surgery and travel back in time to Birmingham’s amazing industrial past, all under one roof? Thinktank, that’s where! From steam engines to intestines, Thinktank has over 200 interactive displays on science and discovery from the past, present and future.
Sodium bicarbonate rockets have been voted 
