Sowing Gardeners with short growing seasons may want to start their Waltham Butternut squash seeds indoors a month before the last expected frost.
Since squashes do not take well to transplanting, peat pots are the best option. Plant two seeds per pot, later clipping off the weaker seedling.
Harden the seedlings by exposing them to the weather for several hours at a time during the week before transplanting.
About a week after the last frost or when the soil temperature reaches an average of 60 degrees F, plant the seedlings in very rich soil 8-10' apart in rows 10-12' apart.
Another option is to plant the seedlings in hills of two, 8-10' apart. To direct sow, plant the seeds a week after frost 1/2" deep, 3-4' apart and thin to 8-10' apart.
Growing Since squash seedlings do not tolerate frost, provide protective coverings if cold weather threatens. Keep the soil moist at all times, but avoid getting the leaves wet as this can cause diseases such as rot or mildew.
When the vines begin to develop, a layer of mulch will help conserve moisture and control weeds; mulch also will keep the squashes clean and protect them from too much soil contact.
By midsummer, pinch off all the blooms to concentrate the plant's energy on the developing squashes. Waltham Butternut resists the squash borer.
For companion planting benefits, plant winter squash seeds along with corn but avoid planting them with potatoes.
