Talk about the different parts of a flower whilst looking at photographs or real flowers in the garden. Try to use accurate vocabulary like stem, petals and leaves. You could even challenge yourself to use ambitious vocabulary like anther or stigma! Maybe you could draw and label a picture of a flower. Do some planting and growing, if you have enough, you could put your plants in different places and see how this affects how they grow. You could put one in a cold place, one in a warm place, one outside, inside, one in the light, one in the dark, water one, don't water one... and see the difference! Chat about what plants need to grow to be nice and healthy.
For some creative fun have a go at making a daffodil using an egg box or painting some tulips by printing with a fork!