Summer squash likes it hot. That being said, there are some southern US climates where squash lovers can still enjoy a Fall harvest of Summer squash. If you live in a western or southern region with Fall temperatures in the 70-90 degree Fahrenheit range, you can have Summer squash in Fall! One reason is due to the short growing season of Summer squash that averages about 50 days. But now is the time to get your seeds in the ground. The following gardening tips for Summer squash also apply when planting for a Summer harvest.
Best Varieties: There are two particular varieties of Summer squash that are possibilities in the right climate for a Fall harvest.
- Early White Scallop: This heirloom variety produces a fruit with a creamy white skin flecked with gold and matching creamy white inner flesh that is delectably sweet. It can be ready to harvest as early as 45 days on vines that can reach 3-4 foot lengths. Tolerant to temperatures as low as 65 degrees Fahrenheit, warmer climates might be suitable for an early Fall harvest. ( image)
- Black Beauty Zucchini: 6-8" fruits are produced with a dark, robust green skin and creamy white flesh. Mature height is only 12-24 inches and grows as a bush. This makes it possible for a Fall harvest container garden that can be moved inside if warm southern days transition to too-cool southern nights. ( image)
Sowing Seeds: Squash doesn't like to be transplanted. That means you want to start from scratch with seeds that are sown directly into their permanent garden spot. Squash is a heavy eater. Prepare a fresh planting area that hasn't been used to grow squash for at least 2 years prior. Prepare soil by enriching with organic matter or compost.
Squash also produces a shallow root system that needs adequate drainage. Break up any compacted soil. Add sand if drainage quality needs improvement.
Sow 1-2 seeds about 1" deep, then lightly cover with soil. If not planting a container garden, use mounds, rather than rows, to orient squash plants. Vines like to spread out. Mounding helps the plant keep its shape and makes more efficient use of space. Space mounds at least 3 feet apart.
Seedlings: Within 7-14 days, expect to see the appearance of seedlings. Thin out the weakest after the first two sets of leaves have appeared.
Crop Size: One last early Fall harvest of Summer squash will produce more than you might think. On average, a single, typical zucchini plant will produce 3-9 pounds. Know what to expect and plan accordingly when it comes time to harvest.
Watering Methods: A drip system is the best method to deliver water to your Summer squash garden. The root system of Summer squash loves water but the plant itself, not so much. Too much moisture above ground can lead to fungal problems. However, if you must water the old-fashioned way, do so in the early morning where a warm, sunny day will evaporate water that pools in leaves and stem joints.
How Much Water? Squash is a very thirsty plant with a shallow root system. In order for roots to soak up the weekly 1-2 inches of water the plant needs, a weekly drenching of 6-8 inches of water is adequate for a traditional garden plot. Mulching will help conserve water usage. If Summer squash is being planted in a container garden for a Fall harvest that can weather cool nights indoors, watering may need to occur more frequently.
Fertilizing: Compost is the best nutrient enrichment for soil. By preparing soil properly before sowing seeds, gardeners will have less need for additional fertilizer treatment. Mulching plants will also provide additional nutritional benefit while also helping to conserve water. Once every two weeks throughout the growing season, give plants a boost with an application of compost tea. Steep a handful of compost per gallon of water for about 48 hours then apply.
Pest & Disease: The most common problems that plague Summer squash are the insects that love to munch on the plants. But diseases attributed to fungus and various bacterial strains can also cause problems.
- Cucumber Beetles: This nasty pest causes the disease, bacterial wilt. It may be present before pollination has occurred which means a gardener can't use the simple solution of a good pesticide spray. As soon as leaves show signs of wilting, inspect for the tell-tale signs of black and yellow striped or spotted beetles. A counter attack of ladybugs or lacewings are good treatment strategies. But beneficial insects only eat the eggs, preventing future infestation. It's up to the gardener to pluck and remove the adult beetles. If there are too many to pick off by hand, spot treatments with organic insecticide on the underside of leaves may be necessary and shouldn't affect pollinators.
- Vine Borer: This insect attacks the main stems, feeding on juices. The first noticeable signs are sudden halt in growth and plant wilt. If an inspection of the base of the plant reveals a residue that looks like fine sawdust, you have vine borer problems. At this point the battle has most likely been lost. That is why an application of preventative is important to young seedlings. An organic pesticide applied to the base of young seedlings, and consistently re-applied throughout the growing season as recommended, will stop vine borers from setting up residence in your plants.
- Gummy Stem Blight: Also called black rot fungus, this fungal disease attacks the tissues of plant stems and is highly contagious. It can strike at any time of a plant's life cycle. The fungus prefers warm, wet conditions. When active, plants will develop black, dead tissue that appears as soft spots. Progress can be halted if action is taken immediately. Remove affected matter and apply a recommended organic fungicide. Powder form may be preferred since a spray introduces more moisture and moisture is part of the problem.
Harvest Time: When the skin is easily pierced with a fingernail, it's time to harvest. Small pruning shears should be used to snip stems, leaving an inch or two of stem-length on the fruit. Many Summer squash varieties are not as sweet as Winter squash. This makes Summer squash the perfect addition, raw and fresh, to salads or even for dipping. Savory soups enjoy richer texture when chunks of zucchini are added. White scallop is tender and perfect steamed, sauteed or added to your favorite stir-fry recipe. Slice up both varieties, add to shish-ka-bobs and grill up a healthy, fresh Fall picnic.
Storage: Summer squash is best enjoyed fresh. The skin is thinner than Winter squash so long-term storage is not an option. Although a pumpkin may last for months as a Fall decoration or stored in the root cellar, not so for more delicate Summer squash. If not eaten right away, store in the vegetable bin of your refrigerator for up to one week. Otherwise, make purees or cube or shred and freeze. But don't forget to save some seeds for next Summer's garden!
Get Some Seeds: Summer squash is really a cinch to grow. Even a rookie gardener can enjoy success with their first effort if they follow tips from experienced gardeners. The key is in the soil. Although foliage and fruit get all the glory, it is the soil that ultimately determines the quality of your yield. Invest the time and effort to prepare a great soil bed to receive seeds and reap a bountiful harvest. Contact a trusted gardening professional to order seeds today!