OBSERVING SEEDS SOWN IN DIFFERENT TYPES OF SOIL
Materials: At least 12mustardor radish seeds, four small flower pots,
differentkindsofsoilcontaininggravel, sand, clay,andhumus.
Follow this procedure:Soaka dozen seeds in tapwaterovernight.
Fill each of the flowerpotswith a different type of soil. Plantthree seeds
in eachpreparedpot. Watereach one until it is moist butnotsoaked. Every
otherday youshouldwaterthe seeds.
You will observe:In lessthana week, seedlings will begin to grow in each
pot. Ifyou have kept them in the light and given them sufficientwater,they
willcontinue to grow, but the seedlings in the pot containinghumus will
grow the fastest and will be thehealthiest.
Before the seedling grows above theground,the baby plantgets all the
nourishmentthatit needs from the seed. Butafterthe first green leavesappear,
they needmineralsas well aswaterandcarbondioxide to help them produce
food for theplant. Ofthe four types of soil you used, onlyhumuscontains
the mineralsthatthe growingplantneeds.GROWING PLANTS FROM PARTS OTHERTHANSEEDS- VEGETATIVE
PROPAGATION
Materials:A whitepotato,a sweetpotato,a carrot,anonion,a narcissus
bulb, a garlic head, afour-inch branchof English ivy,philodendronor ger-
anium. You will also need sand, toothpicks,adarkgreenjar,two saucers,
twoadditionalglassjars.
Follow this procedure: Cutthe whitepotatointo three parts;each part
shouldcontainseveral"eyes." Planteach piece in wet sand.
Suspenda sweetpotatobyplacingit in the neck of ajarof water. If you
putseveral toothpicksin it, they willsupportthe potatoas they rest on the
rimofthejar. Thewatershouldcover thebottomofthe potato.
Cutaboutone inch off the top of acarrot. Set this in a smallsaucerof
water. As thewaterevaporates,addmore-neverlet the dish get dry.
Place an onionand a head of garlic each in a separatejaror glass of
water. Usetoothpicksto keep them partiallysubmerged,justas you did with
the sweetpotato.
Place anarcissusbulb sothatit restspartiallyin wet sand or pebbles.
Cutoff a smallbranch(aboutfourinches) of ivy,philodendron,or ger-
aniumjustbelow a node, thepointwhere the leavesjointhe stem. Place this
in adarkgreenjarofwater.