Been trying to grow pumpkins (jack-o-lantern types) for the grandkids for a couple years with limited success. Any tips (direct sow vs pre-start etc.) are welcome, know there are some good growers on the forum. Have a mostly clay soil up here.
Thanks for the information, been doing some of what's provided but clearly not enough. We'll give it another try and see.Go to Holmes seed website. Pick varieties with powdery mildew tolerance. I can personally recommend Superior and Summit.
Plant around the first week of June.
Fertilize with something like 12-12-12 @ 10-15 lbs per 1000 sq ft. Spread around the whole patch, not all close to the hill. You can put 1/2-2/3 at planting and the rest when the vines start to run.
Plant in hills, 3-4 seeds 5-6 feet apart.
Mulch is good.
Spray with something like sevin to control bugs starting about a week after emerging. Watch for aphids, malathion will control them.
Fungicides are tougher in a home garden. Copper and sulphur fungicides are probably your best bet.
If you water avoid wetting leaves, lay the hose on the ground to soak the soil, not the leaves.
Sorry I missed the part in the OP about clay soils. Adding sand at seeding isn’t enough. The biggest problem with heavy soils is increased disease pressure because the pumpkins sit on damp soil. Especially Pytophera which is a disease that is much worse on heavy soils and not many chemical solutions. Mulch can keep the pumpkins off the ground and limit mud splashing. Crop rotation is best solution but very hard In home gardens.@Ohiosam It sticks in my mind that I heard once they grow better in loose sandy soil? Would he benefit from mixing in some sand where he seeds?
The guys the grow giants have all kinds of crazy tricks. The milk trick supposedly helps get calcium into the pumpkin.Is Milk injections a valid concept for jumbo pumpkins? Seems I heard that somewhere.