Planning on planting hugel this weekend, need advice.

I built the 8'x 4'x 5'tall hugels last fall and seeded early this spring with radish and other things. The growth has been less than stellar so far. Just some little seedlings.
I'm thinking I don't have enough soil over the top of the entire hugel(1'' to 3''), my plan is as follows, please let me know if I'm miscalculating anything.

I'm going to add soil another few inches, pack it on the sides and mulch with chicken bedding, leaves, and woody stick waste the power company trimmed last summer.
Plant squash/melons on top and let the vines trail down into the moist soil between the hugels, or would it be better to let them climb up from the bottom? Hmm
Add some other plants/herbs in various spots to see where microclimates might aid/hinder things.
Nitrogen fixer shrubs will be planted in various places, likely on the north/west side of the hugels to aid in sun and heat capture and for chop and drop mulching.

Any other suggestions? I figure the squash/melon would make for a pretty solid amount of plant material for stabilizing the hugels a bit and help add roots/green for future considerations. Plus a nice harvest.
Thanks!

I find that the plants on top of the hugel don't do as well as the ones at the base. Maybe it takes a while for the roots to bore down from the top to where the nutrients are. My healthiest plants (and weeds that I let grow) are at the base where the hugel starts to rise out of the ground. There I get plants that are 3-4 times the size of ones on top or other places in the garden.

With this in mind, I would say plant your squash and melons low and then assist them to climb up and take over the top.

Hi Russell
I have had the same experience as John. The top of the mound will be warmer and drier than normal or typical so plant choices for this part of the mound should take that into effect.
Just like John has suggested the base of the mound has more moisture and appears to have more nutrient availability.
Saying that, I do find squash does very well on top of a mound with the added warmth.
Soil depth also plays a big role, not enough soil will create a tough environment for your new seedlings to thrive in.

Thanks,
Yeah I can see the value in the moisture at the bottom, that was the main reason I built the hugels was to lessen watering.
any suggestions for dry soil crops at the top? I'm assuming the squash will just take over eventually, but I'd like to have a variety of things poking out if I can.
Thanks again

I'm coming around to thinking that the top of the hugel should be for transplants. Any transplants. While seeds have a difficult time sprouting, little 4" tall seedlings do quite well. Once they figure out there is all that organic matter beneath them. They kind of sit for a couple weeks, not doing much of anything (while the roots are exploring), and then all of a sudden they take off.

Planted my 6 hugel beds with squash and melon seeds, finding the soil quite variable which is probably not good, but I had enough seed to experiment a bit and planted some on top, both sides, front, bottom, and back.

I'll poke some beans in here and there today and maybe some herbs/random things where I see space.
I'm hopeful at least a handful of the squash will grow and fill in over the mounds creating a shadier, wetter environment on the tops and vining in, around, and over the mounds so that this fall when I add mulch the soil structure will be better for next year.

Thanks for the advice, we'll see what happens!

Year 2 hugels. Added soil and packed any gaps full. Added mulch for this year, last season the lower parts worked great, unfortunately I planted most things higher. Radishes, turnips, and mustards self sowed themselves from last year and I've already been getting salads off those greens since early April.