By Joshua Siskin
Q: I’m hoping you can help me with my pumpkin problem. For the past few years, I have planted pumpkin seeds, mainly for my granddaughters to watch the growing process. I always get beautiful flowers, but never pumpkins. I have been advised regarding the necessity of bees and pollination. I tried pollinating the flowers myself, with no luck. I also take note of how huge the pumpkins are at the market, and even with pollination I doubt they would be of good size. When is the best time to plant the seeds? I did that in June, but wonder if I should allow more time for growth. Any suggestions you can give me would be greatly appreciated.
— Charlene Stevens, Valencia
A: Although Halloween is not too far behind us, it’s not too early to set aside a place for a pumpkin patch. For your convenience, any long and narrow piece of ground — whether a side yard, a planter adjacent to a driveway or garage, or a parkway strip between sidewalk and street — is appropriate for growing pumpkins. So if you are pondering what to do in any of the above locations that may currently be bare, and insist on doing something now, consider planting native wildflower seeds and/or winter vegetables. By the time pumpkin planting season comes around in late spring, your wildflowers will be all bloomed out and your winter vegetables harvested.
You don’t need a farm to grow pumpkins but you do need all-day sun, fast-draining soil that is well-composted, and a ready source of water. No, pumpkins are not for a drought-tolerant garden or for any garden, per se, since they require their own space to roam. Vines may trail along for 20 feet or more and you would not want any plants seeking their companionship to get in the way.
If you wish to grow large jack-o’-lantern pumpkins (Cucurbita pepo), you will want to allow four months for them to reach full size. This means you should plant their seeds in late May or the first week in June. ‘Connecticut Field’ and ‘Howden’ varieties are recommended by Jack Creek Farms, a pumpkin grower north of San Luis Obispo.
Pumpkins require rich, well-composted soil and readily available minerals throughout the growing period. Use of a slow-release fertilizer, such as Osmocote Flower and Vegetable Plant Food, is therefore advised. Pumpkin seeds should be planted in the center of the area in which their vines are to spread. Seeds should be planted 1-inch deep, either end up, on flat ground where soil drainage is good or where drainage is less than perfect, on mounds that are 3 inches tall and 12 inches wide in diameter. Seeds may be planted in groups of six and then, as they become seedlings, thinned to three baby plants. Water frequently at first and as plants mature water when soil starts to dry out or leaves are just beginning to wilt. Water copiously and deeply but only as needed. Keep water off of foliage to prevent mildew. When pumpkins begin to turn orange, decrease watering and, to increase storage life, cease watering completely one week before harvest. Harvested pumpkins protected from sun and frost will store throughout the winter.
Pollination requires patience. Male flowers appear two weeks or more before female flowers, the latter recognizable by the presence of bulges — that are actually rudimentary pumpkins — between stem and flower. If you have lots of bees around, pollination will take place on its own. If not, you will have to pollinate manually. You will know that it’s time to pollinate when pollen sticks to your fingers when you touch the stamens of the male flowers. Once it is clear that pollen is available and female flowers are fully open, remove the petals of a male flower and detach the pollen laden clump of stamens that remain. Brush the entire clump of stamens over the stigmas of a single female flower, making sure that all stigmas are touched by the pollen. There are many more male than female flowers on a pumpkin vine so pollen will never be in short supply. Be aware, however, that female flowers stay open for no more than a day so that if they are not pollinated immediately, the little pumpkins beginning to grow beneath them will never develop.
Thanksgiving cactus
Transitioning from Halloween to Thanksgiving, I saw a so-called Thanksgiving cactus (Schlumbergera truncata) in full bloom the other day and was reminded why this is considered one of the most glorious selections for container planting in the Valley, whether we are talking about an indoor, a patio, or a balcony location. Let no one complain that they cannot grow something beautiful because they live in an apartment with little sun. Although the plant pictured with this column is next to a kitchen window that faces south, there are trees outside that effectively filter out most of the sun’s rays.
Native to the cool tropical rain forests of Brazil, the key to flowering these plants is to expose them, starting in September, to night temperatures between 50-60 degrees. It’s also advisable to fertilize once a month between March and August with any all-purpose, water-soluble indoor plant fertilizer at 1/4 the recommended dose. From September to March, cease fertilization and water sparingly, just enough to keep soil minimally moist.
Clarification
In last week’s column, Dothiorella canker, which afflicts avocado trees, was mistakenly identified as a bacterial disease of avocado. In truth, Dothiorella canker is caused by fungi. Thanks are owed to Dr. Akif Eskalen, a plant pathologist at UC Riverside, for this clarification.
For more information about area plants and gardens, go to Joshua Siskin’s website at www.thesmartergardener.com.. Send questions and photos to Joshua@perfectplants.com.
