French hydrangea flowers for 5 to 9 weeks in late spring or early summer. The mophead or lacecap flowers develop from buds formed in the tips of stems the previous year (on old wood). Most older cultivars bloom just once.
Scientists discovered, and have confirmed, that sulfur dioxide (SO2) and nitrogen oxides (NOx) are the primary causes of acid rain. In the US, About 2/3 of all SO2 and 1/4 of all NOx comes from electric power generation that relies on burning fossil fuels like coal.cid rain is a broad term used to describe several ways that acids fall out of the atmosphere. A more precise term is acid deposition, which has two parts: wet and dry.
Power stations give out sulfur dioxide, which is thought to be a cause of acid rain [acid rain: Rain that contains a high level of acids.It is believed to be caused by pollution and, maybe, natural activity such as volcanic eruptions. ] .The amount of sulfur dioxide given off by a power station can be reduced by: 1  removing sulfur from natural gas and fuel oil. 2  removing sulfur dioxide from the flue gases emitted by coal-burning power stations.ulfur dioxide. Power stations give out sulfur dioxide, which is thought to be a cause of acid rain [acid rain: Rain that contains a high level of acids. It is believed to be caused by pollution and, maybe, natural activity such as volcanic eruptions. ] .