More why-does-he-bother data!
Two attachments. The first with an Excel chart showing land use across a range of categories in our two local wards. The second showing data only for all Haringey wards.
Looking at the data across other the other inner/near-inner London Boroughs (Haringey, Hackney, Tower Hamlets, Greenwich, Lewisham, Southwark, Lambeth, Wandsworth, Brent, Hammersmith & Fulham, Kensington & Chelsea, Camden, Islington, Westminster, City), some comparison stats for the 270 wards across those boroughs include:
Percentage of total land as domestic gardens - Harringay Ward ranks 98th out of 270, St Ann's ranks 119th.
Percentage of total land as green space - Harringay Ward ranks 54th out of 270, St Ann's ranks 128th. (Alexandra Ward ranks 11th and surprisingly, for me, Belgravia 4th.)
Both attatched documents contain links to the Department for Communities & Local Government web page from where this data was extrapolated. Should you so wish, you can download a spreadsheet from that site showing simillar data for the whole of the UK.