Doesn't sound like the problem is too much sun because I know holly trees are very dense and probably keep your raised bed in total shade.

Probably not a PH issue either, since both the Lamium and Pulmonaria prefer a slightly acidic soil, which you likely have under your holly tree.

Sounds like a soil problem. Evenly moist but well-drained soil is really important for both Lamium and Pulmonaria, so I'm wondering what the soil moisture is like in your raised bed. Was this bed prepped with compost at all before you planted?

"Evenly moist but well-drained" sounds like a contradiction, but it just means keeping the soil not sopping wet, but, at the same time, the soil should not be allowed to dry out completely at all. Not too wet, not too dry.

A good way to test if your soil is evenly moist or not is to grab a handful of soil and squeeze it into a ball. If water comes out when you squeeze, the soil is too wet. If it completely crumbles and doesn't form a ball at all, it's too dry. What you want is a soil where, if you take the handful of soil and squeeze tightly, the soil will form into a ball, but if you poke your finger into the ball, the ball will fall apart.

The best way to help your soil become more evenly moist is not necessarily watering more or less, but by amending the soil with an organic compost. Over time the addition of compost will improve the soil drainage, and it will also help the soil retain even moisture. More watering or the addition of fertilizer will just not have the same effect...the millions of little microbes in the compost is what helps the soil.

Since your Lamium and Pulmonaria are already planted, I would just side dress the bed with compost. A side dressing of compost will also act like a mulch and help to keep the soil cool. This will help both these plants which prefer a cool soil.

If you didn't add compost to the bed before planting, and a side dressing doesn't work, you may need to amend the soil in the entire bed with compost. This is a more drastic step, and I would ask someone on the "Soil, Compost and Mulch" forum about the best time of year and method for a full bed amendment.

For more info on "side dressing" see the link below.

Here is a link that might be useful: Soil, Compost and Mulch forum: Side Dressing

Problem might be too little sun rather than too much. I grow lots of both lamiums and pulmonarias and find that they need a whole lot more light than most folks think. They both will die off in 1 season in dense shade under deciduous trees so I imagine under holly would be worse. I grow Trevi Fountain in 5 hours of morning sun for best performance and even have some in 3 hours of early afternoon sun with good results.

George

Lamium is quite a bit more drought tolerant than most think. It is actually a recommended plant for dry shade conditions. I'd guess its current state to be a reaction to summer heat - this is not a plant that appreciates summer heat and humidity in many areas of the country and will die out or go dormant under those conditions.