Forsythia x intermedia
Forsyhtia x intermedia is a vigorous variety that is covered in large deep yellow blooms in early to mid-spring. Plant in sun or partial shade, ideally in moist but well drained soil, although the plants are not very fussy. For the best blooms and to avoid your plant becoming a monster, cut back the branches that have flowered back to a pair of strong buds just after they have finished blooming.
Forsythia will grow to be about 8 feet tall at maturity, with a spread of 10 feet. It tends to be a little leggy, with a typical clearance of 2 feet from the ground, and is suitable for planting under power lines. It grows at a fast rate, and under ideal conditions can be expected to live for 40 years or more.
This shrub should only be grown in full sunlight. It is very adaptable to both dry and moist locations, and should do just fine under average home landscape conditions. It is not particular as to soil type or pH, and is able to handle environmental salt. It is highly tolerant of urban pollution and will even thrive in inner city environments.