Our next door allotment holder allowed one parsnip to go to seed. He now has loads of mini plants as the seed has germinated well. Normal sowing would be April-June for harvesting next November onwards. All neighbours have been invited to help themselves. Which I have done and there is now a nice patch of about 70 plants on my allotment. Average size 2-4 cms of root. This is the way nature would do it I assume but I can find no information on the likelihood of success, any help or protection the plants may need or when the crop will be ready. Will the quality suffer? Will the roots be woody.