Welshonion

What's so good about fruit trees?

I know you said 'tree' but had you thought to start with fruit bushes?  You will get a good yeild from blackcurrants, gooseberries and raspberries.  The yeild is pretty well guaranteed, unlike some of the suggestions up-thread.

As I presume you are not the cook as well as the grower, find out what will go down well in the kitchen.

If you decide on a fruit tree, do a bit of research first, because some fruits and varieties are much more challenging than others.

Carrot Tops

I would be a bit wary about eating carrot tops.  There are differing opinions as to whether they are poisonous or not.  They certainly are for horses.

Yes you can use japonica as a substitute for quince, but if you have ever seen or used  the large quinces you might see them as a poor substitute.  Cydonia (?? Not sure that is correct) are in some greengrocers now.

how to feed an orhcid without keeping it in water??

Don't understand your problem.  Stand the pot up to the top of the roots in water with plant food added for about half an hour.  Drain, replace in saucer.

barren fig

Remember if you cut back the shoots you are cutting off the embryo figs for next year.    At this time of the year they are in the leaf axils right at the top of the branches.  Do look before you cut!  And then look again!

Clematis montana problem

What are wildlife friendly slug pellets?  Friendly to what wildlife?  If you kill all the slugs and snails what will the hedgehogs and birds have to eat? 

rush weed

Ragged Robin for starters.  Water mint near the stream, also marsh marigold, Have a look through a Wild Flower book for inspiration.  Take care not to plant anything invasive like Himalayan Balsam.

rush weed

You will get rid of rush if you improve both the drainage and fertility, but is that what you want?  What do you want to do with the meadow?  Grazing, wild flower meadow?

olives and strawbs

In fact I would remove the straw.  It is only usually put round the plants as the fruit come to ripening to keep the strawberries clean.  If you have straw round the plants in the winter it may attract rot as it will hold the moisture, and it will certainly be a haven for slugs and snails.

collecting and storing seeds

I think it would be a mistake to save sweetcorn seeds as they are probably a hybrid seed.  What you would get is a rather boring sweetcorn, when I presume you were trying to grow a 'super-sweet' one.

The photo you have at the top is the male tassel.  It hasn't been a good year for ripening corn, did you get any?

Beetroot seed will also, I suspect, be a hybrid and not at all what you would like to eat. Buy packets until you are more experienced, otherwise you will  waste your time, money and energy growing inferior vegetables.

Catapillars

The frost will do for them.  Bit late now to plant nasturtiums. Just keep squashing the caterpillars.

Fig Tree Care

Swifts