Forsythia is a popular, easy to grow, spring flowering deciduous shrub.
Forsythia has bright yellow flowers in early spring ahead of the leaves, which form in March through to April. This means the flowers are carried on bare branches and after flowering, the shrub comes into leaf.
Forsythia is popular and many gardeners grow them. Being so commonly seen and grow, some can be sniffy about Forsythia, but its lovely bright yellow is so welcome early in the year I think there is room for one in the garden, at least.
Also, Forsythia is so easy to grow, you can just plant and neglect. Forsythia does flower best in full sun, but they will tolerate light shade just produce a few less flowers. Forsythia is tolerant of all soil and growing conditions except boggy ground.
Forsythia is can grow up to around 3 metres and is fully hardy. Two varieties which have the RHS merit award are Lynwood and Arnold Giant. We tend to think of Forsythia as a largish shrub but there are smaller, more compact varieties such as Forsythia × intermedia 'Mikador', Forsythia Dwarf Mini Gold, Forsythia 'Fiesta' which grows to around 1m- 1.5m. Smaller more compact varieties of Forsythia will require very little pruning. There is also variation in colour from the bright strong yellow to a paler yellow.
Forsythia will grow more or less anywhere and in most aspects, which is why they are so popular, coupled with the fact Forsythia requires no real attention from one year to the next.