What are folks seeing now?
In some places, plants have entered the "Flowers or flower buds" phenophase. At other sites, flowers have yet to appear.
What you see depends on where you observe. Although this makes it difficult to predict exactly what you will see when, it reinforces how important your observations are. Pesky Plants research is improved by having observers in a variety of locations. Your observations matter!
Checking for initial growth of knotweed
If possible, gently lift and then replace debris that could obstruct your view of shoots or early leaves. Materials such as dead leaves and other debris can play an important role for newly emerging plants by regulating their microclimate. Every site is slightly different so find a balance between detecting early signs of growth and leaving site conditions unchanged.
Locate plants: Volunteering works best if wild parsnip or knotweed plants grow nearby, in a place that is accessible and convenient to you. If you're unsure if these plants can be found near you, check out these resources on locating wild parsnip or knotweed.
Observe plants: Begin observing plants when you are ready. (There is no point in the season when you are "too late.") Record what you see using Nature's Notebook.