How can I get rid of blight on my vegetable plants?

Liquid dish soap (Dawn) and Listerine work for me!

What type of weed block?

MILK--To use milk as an anti-fungal spray:

1. Mix 1 part milk to 2 to 3 parts water in a spray bottle.
2. Spray the solution onto the leaves of plants, preferably unaffected plants, when the plant is in bright sun. Soak both sides of the leaves until the solution is dripping.
3. Repeat the spray application every 10 to 14 days.

BAKING SODA---Step 1: Mix 3 tablespoons baking soda with 1 gallon of water.This is the baking soda we use: Arm and Hammer PureBaking Soda. Step 2: Mix in 1 tablespoon vegetable oil, or cooking oil of your choice. This helps the spray to stick to the leaves. Step 3: Mix in 2 drops of dish soap to help emulsify (mix) everything NEEM OIL---To apply, mix 1.5 Tbsp of neem oil with 1/2 teaspoon of non-toxic liquid soap(castille) per gallon of water and shake like crazy before and during application. This makes for a 1:170 ratio of neem oil to water (1:150 to 1:200 seems to be the norm). That amount will do about 250-500 square feet, but don’t spray too much on young seedlings – it’s better to wait until plants are bigger for most types of foliar spraying, as tiny plants can be quite vulnerable to overapplication. Here's great info. on Neem oil many other benefits for garden pest control https://www.smilinggardener.com/sale/pure-neem-oil-for-plants/

For your soil problem, You might consider raised beds with good soil. I have clay and rock on top of a bluff and have tried to amend the soil, but illness has kept me from doing this so I build raised beds for vegetables, herbs, any plant that requires good drainage.I also have vegetables like tomatoes, peppers, lettuce and onions in large pots on the deck that I move inside for the winter. It is February 23 and I am still harvesting salads.