Garden Life. Unit. Year levels 4 5. About this unit. Preparing for the unit. Garden and kitchen classes. Curriculum Links. Science: Understanding

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1 Unit Year levels 4 5 Garden Life About this unit : Understanding living things have life cycles (ACSSU072) living things, including plants and animals, depend on each other and the environment to living things have structural features and adaptations that help them to survive in their environment (ACSSU043). : Inquiry Skills with guidance, identify questions in familiar contexts that can be investigated scientifically and predict what might happen based on prior knowledge (ACSIS064) suggest ways to plan and conduct investigations to find answers to questions (ACSIS065) decide which variable should be changed and measured in fair tests and accurately observe, measure and record data, using digital technologies as appropriate (ACSIS087) use a range of methods including tables and simple column graphs to represent data and to identify patterns and trends (ACSIS068) represent and communicate ideas and findings in a variety of ways such as diagrams, physical representations and simple reports (ACSIS071). The unit investigates the things that plants need to survive, including food (nutrients), water, sunlight, shelter and the means to reproduce. The principles of plant pollination and dispersal are explored, as are organic strategies for controlling pests. Preparing for the unit This unit works best when some of the kitchen garden plants are in flower and some are fruiting. Otherwise, it will be necessary to purchase a small selection of fruits and vegetables from a local greengrocer. It is essential that a selection of flowers is on hand for students to investigate. These can be sourced from the kitchen garden or brought to school by the class. Before the unit commences, students can bring seeds in from home or collect them from the garden. These should be kept in small paper bags or envelopes and labelled with the type of plant they come from, such as tomato seeds, mustard seeds, sesame seeds. Garden Specialists and volunteers play an integral role in the unit and it is important that they are aware of what is planned and are involved accordingly. Garden and kitchen classes The unit will be enhanced if the Garden Specialists and volunteers reinforce the ways that the needs of plants are met in the kitchen garden. Further, incidental teaching about pollination and seed dispersal will be invaluable, as will students participation in organic pest control, mulching and composting.

2 Garden Life Lesson 1 The Needs of Plants living things have life cycles (ACSSU072) living things, including plants living things have structural environment (ACSSU043). The classroom and the kitchen garden 60 minutes Getting started Ask the class to make a big list of all the things they need in order to survive. Their suggestions might include food, water, shelter, health care, sleep, money, exercise, transport. You might want to distinguish between items that are essential and items that help obtain the essentials. For example, money and transport will not support life by themselves but they help us obtain essential items like food and shelter. During the lesson Students consider what plants need to survive and vary the list of needs on the whiteboard accordingly. Their new list should include: food (or nutrients), water, sunlight and protection from plant-eating animals. Compost and manure are sources of food and help retain water. Mulch provides protection, water retention and, in some cases, food. If stakes and trellises or similar supports are suggested, this can generate interesting discussion about how wild plants would survive without someone to stake them. Many plants that rely on staking in our gardens grow wild in dense vegetation and are supported by the surrounding plants. In the garden In the kitchen garden, students form small groups and identify ways that each of the survival requirements is provided for the plants. Examples include: location of the garden to capture sunlight, water tanks, irrigation, mulch, compost, manure, trellises and scarecrows! Assuming compost and manure are used as food for the plants, you could point out that kitchen garden plants depend on other plants and animals for food. In the classroom Back in the classroom, students share their findings about how plants needs are met. These can be recorded on the whiteboard or displayed on a poster. Following up Students continue to bring labelled seeds to class. In Lessons 5 and 6, the ways in which plants can be protected from herbivorous pests will be explored further. noting their responses to questions.

3 Garden Life Lesson 2 Reproduction: Pollination living things have life cycles (ACSSU072) living things, including plants living things have structural environment (ACSSU043) with guidance, identify questions in familiar contexts that can be investigated scientifically and predict what might happen based on prior knowledge (ACSIS064). Resources flowers, preferably from plants in the kitchen garden. At least two flowers should be from the same type of plant labelled seeds brought to class by students The classroom, the school grounds and the kitchen garden 75 minutes Teacher s note Methods of pollination are diverse among plants, and while the process described in the following lessons is common in the kitchen garden, it is important to avoid giving the impression that this is the only method of pollination in the plant world. Likewise, the range of animals that pollinate flowers and disperse seeds is much broader than the small sample described for the kitchen garden. Getting started Students revise the needs of people and plants listed in Lesson 1. During the lesson Ask the class, If no more children are born in the world, will people still exist in two hundred years? Prompt students to make the distinction between the survival needs of an individual and the needs of a species. In order for the human race to survive, we must have children (we must reproduce ). Ask, What about plants? If plants don t reproduce, will they still exist in one hundred years? As a class, brainstorm ideas about how plant reproduction works or what it might involve: seeds, flowers, seedlings, baby plants, etc. Make a list on the whiteboard. Explain that flowers are an essential part of plant reproduction. In order for plants to reproduce, pollen from one flower must be transported to another flower of the same type of plant. For example, pollen from the flower of one capsicum plant needs to be transported to a flower of a different capsicum plant. Using a selection of flowers, the teacher and the students locate the pollen. Explain that pollen sits on anthers. In the garden Take the class outside to find flowers in the school grounds. Locate the pollen in each flower. While outside, pose the question, How do you think the pollen from one flower is transported to another flower? Answers might include: Nutritional value Fun factor, novelty, or other emotional responses Exploring new combinations and trying new flavours Using the produce from our garden Environmental considerations: food miles (ingredients from our garden have travelled the fewest miles to get to the kitchen) versus the emissions of the delivery van or parent who will go and collect the pizzas (this will depend on how far you are from your local pizza shop)

4 Garden Life Lesson 2 p2 In the classroom Repeat the question about how pollen is transported from one flower to another. Start a class list of new ideas. Because the means of transportation are many and varied, it is advisable not to discount any answers, but rather indicate that improbable suggestions are not the answers the class is looking for. The most common method of transportation of pollen between flowers in the kitchen garden is on the bodies of insects and birds. Some of the most common pollinators in the kitchen garden are bees and butterflies. When a bee visits a flower, it gets pollen on its body and legs. When the bee visits another flower, some of the pollen brushes off on the new flower. This enables the new flower to begin forming seeds. Seeds are the beginning stages of new plants. Using the collection of flowers to prompt their responses, students consider how flowers attract pollinators. Bright colours, smell and, most importantly, food are some of the key attractors. Many pollinators, including honeyeaters (birds), bees, moths and butterflies rely on nectar, the sweet liquid inside flowers, for food. Finishing the lesson Visit the kitchen garden with the class again to see if any pollinators are at work. This is less likely to be the case in the cooler months of the year. Following up Key words can be presented on displays or flashcards in the classroom: anthers, nectar, pollen, pollinators, reproduction, stamens. You might choose to discuss the role of stigma, which capture and trap pollen from pollinators. noting and recording their understanding of pollination and seed dispersal.

5 Garden Life Lesson 3 Reproduction: Dispersal living things have life cycles (ACSSU072) living things, including plants living things have structural environment (ACSSU043) with guidance, identify questions in familiar contexts that can be investigated scientifically and predict what might happen based on prior knowledge (ACSIS064). Resources fruit that contains a range of different seeds knives for cutting fruit labelled seeds brought to class by students The classroom, the school grounds and the kitchen garden 45 minutes Seeds contain lots of nutrients so that the plant will form and grow. This is why they are usually so healthy to eat! What foods do you eat that contain sesame, pumpkin and sunflower seeds? Teacher s note As noted in Lesson 2, methods of pollination and dispersal among plants are diverse. While the process described in the following lessons is quite common among plants in the kitchen garden, it is important to avoid giving the impression that it is the only method of dispersal in the plant world. Getting started Review the information about reproduction from the previous lesson. Students identify where the seeds in their collection came from. In many cases (though not all), the seeds will have come from the fruit of a plant. During the lesson In the classroom or kitchen, students halve the fruit to locate the seeds. Ask them to note size and approximate number of seeds, and where the seeds are found in the fruit. The seeds can be added to the class collection. Students can draw diagrams to record cross sections of the fruit and the seeds. Ask, Why do plants put their seeds inside fruit? Record all of the responses on the whiteboard. These may include: to protect, hide or provide food for the seeds. Because the reasons for encasing seeds in fruit are diverse, it is advisable not to discount any answers but indicate that improbable suggestions are not the answers the class is looking for in this discussion. To provide focus to the question, ask, Why would plants put their seeds inside a fruit that is soft, smells good and tastes delicious? You might prompt the response that the plant wants animals to eat the fruit and the seeds in it. Ask, What happens when an animal eats a fruit? When an animal eats a seed, it might crawl, walk, jump or fly some distance before it expels it (that is, poops it out). In this way, plants can spread their seeds over large distances without having to move. And everyone knows that animal manure is very good for plants to grow in! Many animals disperse seeds, including parrots, honeyeaters (which also pollinate flowers when they feed on nectar), fruit bats and possums. Fruit grown in the kitchen garden is eaten by people so the seeds are not dispersed by animals. If we want to plant new seeds we must first collect them from the mature fruit. Following up In a kitchen garden class, students plant seeds from the class collection, in the garden or in seed boxes. noting and recording their understanding of pollination and seed dispersal.

6 Garden Life Lesson 4 Reproduction: living things have life cycles (ACSSU072) living things, including plants living things have structural environment (ACSSU043) represent and communicate ideas and findings in a variety of ways such as diagrams, physical representations and simple reports (ACSIS071). Resources a selection of flowers labelled seeds brought to class by students pencils, crayons, paints, glue workbooks books, magazines for cutting up, websites, and other resources suitable for showing some aspect of plant pollination and seed dispersal Getting started As a whole class, revise the information about plant reproduction learned in the previous lessons. During the lesson Explain that the students must devise a way of explaining plant reproduction. This can be accomplished with dramatic presentations, illustrations, a series of storyboards, pieces of writing, quiz questions and answers whatever means will provide a sound indication of students understanding. Working individually or in small groups, students prepare their display for sharing with the class. You may want to start with a structured thinking process such as a KWL chart (What I Know, What I Want to Know, What I Have Learned) or a mind map to help initiate students investigations. Students make use of classroom resources including books, magazines, the Garden Specialist and websites. On their worksheets, students match the sentences with illustrations, then cut and paste them to represent the stages of plant pollination and dispersal in the correct sequence. These can be displayed in the classroom. noting and recording their understanding of pollination and seed dispersal throughout Lessons 2, 3 and 4. The classroom 90 minutes

7 Garden Life Lesson 5 The Garden s Most Wanted living things, including plants living things have structural environment (ACSSU043) with guidance, identify questions in familiar contexts that can be investigated scientifically and predict what might happen based on prior knowledge (ACSIS064). Resources workbooks digital cameras (optional) copies of the information sheet (on the following page) the Garden Specialist and volunteers The garden and classroom 60 minutes In the garden Students visit the kitchen garden and list the creatures they find. They can also take photos or draw pictures. The class list might include snails, caterpillars, wattle birds, slugs, aphids, ladybirds, magpies, moths, lizards, praying mantis and fruit flies. In the classroom In pairs or in small groups, students classify the list of creatures according to whether they eat plants or animals. These classifications can be refined according to whether the creatures are harmful to the plants, or helpful. Some creatures might exist in both categories; for example, caterpillars do considerable damage to plants but adult butterflies are excellent pollinators. Carnivorous animals are among the most beneficial to plants because they feed on plant-eaters. Lizards, ducks, magpies, ladybirds and praying mantis are among a gardener s best friends. The class makes a list of the Garden s Most Wanted: the creatures who do the most harm to the kitchen garden. The Garden Specialist and volunteers can assist in making the list. Discuss that one way of controlling pests is to use commercial insecticides that contain toxic combinations of chemicals. These are usually very effective in killing pests, but are not always a good idea in the kitchen garden. Students suggest reasons why toxic insecticides might not be suitable. Answers include: insecticides kill both harmful and helpful creatures; toxins are consumed by helpful predators when they eat pests that have been sprayed with insecticide; toxins can remain in the soil for months, rendering fruits and vegetables harmful to people. In short, insecticides introduce poisons into the garden that can do more harm than good. Pest patrol Students form groups to target a specific pest species, such as snails. Each group suggests two strategies for controlling their pest. The accompanying information sheet can assist, and the Garden Specialist and volunteers may provide insight. Each group makes a list of the ingredients and resources they need in order to implement their strategy. To minimise expenditure, agreement between groups might be required to determine which sprays will be used. Following up The teacher, Garden Specialist, volunteers and children prepare sprays. Children bring along additional resources such as egg shells, coffee grounds or soap flakes, as required. Students will implement their plans in Lesson 6.

8 Garden Life Lesson 5 p2 Extension / Variation At this point, you might want to introduce the concept of control groups and fair testing. Have students plan their pest control strategies and discuss the benefit of leaving a group of plants untreated (so that data collected can be compared). In Lesson 6, students will implement their plans but the class will designate a control group. the suitability (or otherwise) of the pest control strategies they identify individual participation and interaction in their group. Related resource Stephanie Alexander s Kitchen Garden Companion provides comprehensive information about organic ways to control garden pests (See pages ).

9 Garden Life Student Factsheet The Garden s MOST WANTED Garden pest Aphids Caterpillars Mealybugs Snails and slugs Thrips Ways to control garden pests Introduce predators such as ladybirds. Spray plants with homemade white oil: 4 parts sunflower oil; one part dishwashing liquid. Dilute one tablespoon of mixture in 4 L of water. Use garlic spray: chop 100 g of garlic and cover with vegetable oil. After several hours, strain and add one litre of soapy water. Dilute 100 ml of mixture with one litre of water. Use soap spray: 3 tablespoons of soap flakes dissolved in 4 L of water. Use chilli spray: 6 small red chillies; one litre of water; one tablespoon of soap flakes. Remove by hand. Sprinkle pepper on wet leaves of plants. Spray plants with garlic spray (see recipe, above). Spray plants with homemade white oil (see recipe, above). Dab bugs with cotton buds soaked in methylated spirits. Remove by hand. Use a coffee spray on plants: one part black coffee (i.e. an espresso) to 3 parts water. Set beer baits: half a bottle of beer laid on its side. Surround plants with egg shells. Spray water under the leaves of plants. Use pyrethrum spray: 1/2 cup of dried pyrethrum flowers; one litre of boiling water. Add one teaspoon of soap flakes when the solution has cooled. Use garlic spray (see recipe, above). Warning! Only use sprays in the early morning or evening. Spraying on warm days can burn plants. Avoid contact between your skin and the sprays. It is best to wear gloves and goggles when spraying. Pyrethrum kills many creatures, including helpful insects like bees and butterflies. Its fumes are toxic when being prepared. Questions to consider: How will we know if our treatment has reduced the number of this specific pest? What will we look for? When will we look? What notes or observations will we write down? Why? Is there anything else we need to consider?

10 Garden Life Lesson 6 Testing Pest Control Strategies living things, including plants living things have structural environment (ACSSU043) with guidance, identify questions in familiar contexts that can be investigated scientifically and predict what might happen based on prior knowledge (ACSIS064) represent and communicate ideas and findings in a variety of ways such as diagrams, physical representations and simple reports (ACSIS071). Resources pest control sprays and resources as listed in Lesson 5 workbooks paper, pencils, marker pens and crayons to make garden maps a class garden map drawn on paper, the whiteboard or another suitable surface the Garden Specialist and volunteers The kitchen garden and the classroom 2 hours In the garden As a class or in groups, students set up experiments in the kitchen garden. First, they select three plants, or three groups of plants. To the first plant/s they implement a pest control strategy from Lesson 5, such as watering under the leaves of plants to discourage thrips. To the second, they implement a different pest control strategy, such as using garlic spray. They do nothing to the third plant or group of plants. In their workbooks, students note the plants they have treated (and not treated), along with the details of the pest control strategies and factors such as date, time of day, wind conditions and cloud cover. In the classroom Students transfer their notes to a class garden map. As a class, discuss various factors that might influence the outcomes of their experiments such as the rain, wind and temperature. Revisit the discussion that took place in Lesson 5: plants depend on predatory animals to control the population of plant-eating animals. You might point out that in the kitchen garden, we don t always have enough carnivores so we sometimes intervene to protect the plant (and our crop!) Following up During the next two weeks, students visit the kitchen garden daily to record the effects of their pest control strategies and compare the outcomes with the plants that received no treatment. Students can then determine whether some strategies were more effective than others. The teacher can introduce the scientific term control group to describe the plants that have not been treated. The control group allows the class to determine the effectiveness of the strategies by comparing treated plants with untreated ones. It is important to emphasise that a combination of pest control strategies is usually the most successful. evidence that students understand the basic concepts of fair testing, comparing observations of treated plants and the control group students suggestions about the factors that might have influenced results discussing the outcomes of the experiments with the class.