We managed to secure an allotment yesterday and it looks huge. I am interested in experimenting with square foot gardening but this isn't going to cover a quarter of the plot.
If you've got an allotment ("Unlimited space", as it were) I am not sure that square foot gardening is your best bet. I think that growing the number of plants you need (to give you the yield you can consume) is your best bet.
For example, Cauliflowers are short-harvest crops - there is only about 2 weeks from when the first is ready to when the last is past its best. No point growing "a whole row"!! I grow 4 cauliflower plants "per batch" and start off a batch every fortnight.
On the other hand Runner Beans crop heavily all summer long, and I grow about 10' of Runners and another 10' of Climbing French.
I grow about 50 Parsnips - that's enough to see us through the winter.
... and so on. Keep a notebook to record what you did, when, and when it cropped, and then make notes about whether you had too much, or too little, and adapt next year.
He has offered to clear the site of grass and weeds using 'Round up' which he says will have no effect on the soil or vegetables we grow but I'm not so sure.
Personally I think that's an excellent idea. Its quite daunting taking on a plot (unless you are already a gardener), and having all the weeds killed off before you start will make the first year easier.
However, weeds need to be actively growing for Roundup to work, so that will mean waiting a while before it is applied, and that may put you "behind" in getting started.
We used Roundup / Glyphosate on our plot to get started, and the plot has had no chemicals on it since as we are keen not to use any pesticides etc on the food we eat. But I would not hesitate to use a single starter application of Roundup if we had to start again.
I have a petrol strimmer so I will attack the grass and weeds with that. I don't want it to turn into a mud bath.
I doubt you will turn it into a mud bath
This route would mean digging the plot, and removing all the weeds and roots as you go. If you are fit that is a reasonable approach, particularly if the plot has been cultivated over a long period in the past, even if not recently, as the soil will be in good heart as a result of years of cultivation.
If there are issues over weeds then covering the plot (with weed suppressing membrane, or cardboard) and "planting through it" in the first year will help with weed control, and weaken the weeds during the year such that next year the battle will be easier. You still need to dig it first though.
Spuds is a good initial crop for clearing the ground
Anyway back to the original title. I would like to put in a large crop of potatoes but there is no point growing a variety that is commonly available in the shops so what I am looking for is an interesting, good tasting potato that is good for boiling, mashing and baking.
I think it is worthwhile growing First and Second Early varieties. They will give you New Potatoes early in the season, they will taste great "fresh", and at a time when New Potatoes are still relatively expensive in the shops.
I'm a lot less sure about main crop. I have great difficulty storing mine well - they tend to sprout and go a bit soft. After months of storage they don't taste any better than shop-bought. Large bags of spuds from farm shops have been stored in temperature controlled conditions, so are in much better condition, and are cheap to buy.
Main crop is also more at risk from blight (although that's probably not a significant reason for not growing them). First and Second early crops are normally "over" before there is risk of blight. However, Earlies don't store well ...
My suggestion would be that you buy several different varieties of Seed Potato Tubers "loose" from the garden centre. You could get just 4 (say) of each variety and then taste them to see which you prefer and grow those in future years. Taste is based on personal preference of course, but your soil and growing conditions will also play a part.