Flipping the switch for summer; planting everything out, losing cucumbers again

After a somewhat cool spring, we've suddenly flipped the switch for summer.  Last Monday I got completely drenched (and even hailed on) on my bike ride home from work and this Monday I was slathered in sunscreen at the beach.  Throughout spring we've had some dry spells and some rainy spells;  while I welcome some heat, I hope we still get some rain this summer and not a hosepipe ban.

I've got my zucs planted out at the allotment, as well as all my tomatoes (both cherry and plum, in containers).  The tomatoes have a good straw mulch to keep moisture in; whereas the zucs are planted in a new sheet mulch, and they won't have direct root contact with the soil yet--I'm watering both of them twice a day in this heat.  The rest of the plants, whether on top of sheet mulch or not, have been growing long enough not to need such copious watering (potatoes, peas, beets, broad beans, cabbages, kohlrabi, Brussels sprouts, garlic).  Except the overwintered onions, also in containers.  Containers need lots of water, no matter the weather.  

I've had somewhat sparse germination of squashes and cucs, and not only that, a lot of cuc losses.  They have been sprouting, wilting, and then shriveling up.  I might not get any cucumbers this year, but I will try one more batch of seed, despite it being a bit late.  This has happened to me in the past, though usually with older plants just starting to produce fruit.  I'm not sure if it's the potting compost (though everything else has been fine in it), the seed (saved my own from last year's fruits), or a cucumber specific disease.   It looks like the squashes are ok, just not a lot of them.  I'll try starting one more batch of these too.

I've grown some flowers from seed both this and last year:  columbine, lupin, verbena, wallflowers, strawflowers, marigolds.  I have some that self seed every year in my garden too:  poppies, honesty, borage, foxgloves, calendula.  There are a lot of ornamentals in my garden:  many shrubs, some bulbs, as well as some herbaceous perennials.  Spring is particularly pretty out back, but it's also lovely now in early summer.  I used to pick myself homegrown bouquets every week;  I got out of the habit around the time I got my allotment, but I really should pick some again even if only once in a while.

Finally, last week I collected my largest plastic plant pots to transplant my chilis and eggplants.  While I've sometimes succeeded with chilis (though not reliably), I've never got beyond two leaves on eggplants.  Until this year:  most of my little plants have at least four leaves!  Will they carry on?  I half filled the pots with partly composted chicken manure that I dug from the chicken yard, then topped up with commercial potting compost to plant into.  Now 10 eggplant pots are on my patio, in the sunniest most sheltered spot, and all possibly looking to grow a fifth leaf;  they are grouped with 12 pots of chilis, with similar leaf count.