Lettuce Bitter again - any thoughts?
This is my 5th year gardening. Every year I get tons of nice tomatoes, onions, peppers, cukes, etc. However, every year my lettuce is bitter. I have tried multiple varieties that I grow from seeds, store bought seedlings, and seed tapes. I water every other day deeply. The lettuce is picked at various stages. Yet always the lettuce is bitter - sometimes mildly and sometimes intensely. Soil testing showed good nutrient and organic matter percentages and the soil p.H. is normal. Any thoughts?
I'd be curious to know which varieties folks in this area grow that aren't bitter. Do local farmers grow lettuce or is the climate just not conducive?
I live in Owings Mills, which is northwest of Baltimore.