Have you had a soil test?

Undersized plants and poor yield are generally due to some kind of problem with the soil. But without a soil test you don't know if your pH is too low or too high, if you are deficient in a particular nutrient or have something to excess, etc.

Its hard to go wrong with compost -- give the plants a generous side-dressing just as the vines start to run and just as they start to set fruit. But contact your local cooperative/ag extension to find out how to get a soil test.

My test this spring was a real eye-opener and, despite my preference for organic methods, the extreme condition called for a bag of 5-5-15 as a temporary measure while I work on long-term soil improvement.

Its amazing what a few, carefully targeted handfuls of fertilizer, some lime (I knew I needed it but didn't know that I needed it in such extreme amounts until I got that test back), and the limited amount of compost that I had ready did for my production.

DOH! I think I figured it out! Here's the description from Johnny's seeds of the variety I planted.

Product ID: 2867
Metro PMR (F1)
(Cucurbita moschata)

Smaller size with powdery mildew resistance.
Attractive, smaller Butternut; just what many markets are asking for. Clearly smaller than Waltham, avg. 2 1/2-3 1/2 lb. Powdery mildew resistance supports better vine health, thus improved sugar and dry matter content and taste. Compact vine. Combines parentage from Cornell University and JohnnyÂs. Avg. yield: 4-5 fruits/plant. Avg. 5,400 seeds/lb. Packet: 30 seeds.
Days to Maturity or Bloom: 105

AHA!

I always grow big squash for my large family so I never even thought to wonder if it were a naturally small variety.

The seed people have developed a number of smaller varieties for containers and smaller families lately.

Yes, I didn't notice because I bought that variety strictly for it's powdery mildew resistance. Didn't pay attention to the size comment. And I bought the seeds last fall after the PM took out most of my squash plants of all varieties. So off I went and bought seeds for PM resistance. This year I just planted those PM resistant seeds without thinking about it. Good news is, so far, none of my squash have PM. They may be small, and the ones other than butternut all got attacted by SVB - most lived - but none have PM by gosh! :)

There are larger cultivar with PM resistance if you need to go that route in the future. Indian Brave ( 4-5 lb), Chieftain,Atlas, for butternuts. Table Princess, Autumn Delight, Honey Bear, Taybelle for Acorns. There are lots of others, but these are the ones I know off the top of my head.
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