As we reach the mid-point of summer, it is time to start planning ahead and planting seeds for fall vegetable crops like cauliflower, broccoli, lettuce, cabbage, kale, carrots and brussels sprouts. With lower levels of light, more consistent moisture, and the occasional light frost, cool weather crops can excel well into the waning days of fall. With some careful planning, you can keep your garden productive well into fall and even winter. At Fort Collins Nursery we have a number of great seed varieties from great companies like Johnny’s Selected Seeds, Baker Creek Heirloom Seed Co. and Seed Savers Exchange. Before you get started it is important to know the following information:
Average First Frost
In Fort Collins, the average first frost date is October 2nd. For those of you in other surrounding areas you can look up your average first frost date through the Old Farmer’s Almanac.
Days to Maturity
To find out the best dates to plant your seeds, you will need to calculate when to plant your vegetables so they’ll mature before being killed by frost and cold. To find the optimal date, simply subtract the days to maturity from the average first frost date in your region. For example, for a vegetable like beets that take 60 days to reach maturity, you would need to plant your seeds between August 3rd based on our October 2nd average first frost. Most seed packs will list information on how many days until the crop reaches maturity. A quick Google search will also yield several examples of vegetable planting guides like this one from CSU Extension.
Certain varieties like broccoli, beans and winter squash are more susceptible to frost while kale and cabbage are more tolerant. If you’re worried about losing your crops to premature frost, you may want to choose from the more cold tolerant crops.
We generally think of spring- a time of new growth and life- as the time to plant everything including trees & shrubs. However, cooler temperatures make fall an excellent time to plant. The soil is warmer than in the spring, and many of us actually have more time to devote to planting trees and shrubs in the fall, when we aren’t so preoccupied with our annuals and vegetables. Fall is a great time to plant, because it gives your new plants time to settle in and gives them a jump start over anything planted next spring.
Trees & Shrubs
- Plant while the soil is still warm (Soil temp. 6″ deep should be above 55 degrees Farenheit) to encourage strong root growth and development. Typically, our soil maintains warm temperatures into mid-October, even after the air is much colder.
- Container-grown trees, (such as all trees available at Fort Collins Nursery), transplant much better than bare-root or recently dug balled-and-burlapped stock.
- Keep newly planted trees & shrubs well watered (but not over watered) until they drop their leaves, and then water them deeply once a month throughout the winter.
- Young thin-barked trees should be wrapped in late October/early November with a breathable wrap to prevent frost cracks, animal damage, and sunscald. Wrap the trunks with wither paper tree wrap or rigid plastic that allows for air movement. Remove the wrap no later than early/mid March. Trees that have developed the coarse craggy bark typically associated with mature trees do not need to be wrapped in the winter.
- Mulch trees with 3-4” wood chips to prevent early soil freezing.
Every Autumn, our garden shop is taken over with a diverse selection of bulbs for spring color! Tulips, daffodils, iris, narcissus, allium, crocus and more are available in a rainbow of colors. These bulbs can be planted up until the soil freezes, but shop early for the best selection! It is best to plant bulbs early in the fall so that the bulb root has time to get established, prior to the ground freezing. Bulbs prefer sandy or clay loam soil. In general, bulbs should be planted at a depth of three to four times the diameter of the bulb. If planting in a sandy soil, plant two inches deeper. Small crocus bulbs should be planted more shallowly; large allium or daffodil bulbs will be planted more deeply. Information courtesy of CSU. We also offer amaryllis and paperwhite bulbs that can be forced to bloom in the winter months. Call or stop by for availability, and chat with one of our knowledgeable staff for how-to tips. We also have all great selection of bulb accessories: gravel, vases, bulb planter tools, books and bulb fertilizers.
As the summer temperatures start to rise above 85 F., many of our plants will inevitably start to feel the adverse effects of heat stress. Heat stress occurs when temperatures are hot enough for a sufficient period of time to cause irreversible damage to plant function or development. Signs of heat stress include wilting, yellowing leaves and drying up. Plants will also drop leaves,, flowers, blossoms and fruits in an effort to conserve water. Unfortunately there isn’t much that can be done for trees and plants that have sustained heat related injury but there are several things we can do to help minimize or prevent heat injury in the future.
It is important to deal with heat stress as soon as you notice it. First, check the soil several inches below the surface to see if it is already damp. If the soil is damp but your plants still look wilted, do not add more water – many plants simply wilt in intense heat (tomatoes are notorious for this), and will perk up once temperatures drop in the evening. However, if the soil is dry, it is important to water your plants immediately (don’t wait until your next scheduled watering cycle as irreversible damage could set in rapidly). Plants in containers should be watered daily and even twice a day in extreme heat. Make sure to give them a good soaking. Trees and shrubs should be watered regularly and deeply with a long slow trickle to ensure all the moisture is absorbed into the root systems. If water is running off dry compacted dirt, give it a short watering to moisten the surface and hit it again later with a more thorough soaking once the ground is able to absorb. Applying organic mulch is a great way to lock moisture into the soil to prevent evaporation and regulate soil temperature. Shade cloth and ground covers will also provide your plants with a little instant relief.
As vegetables grow in your garden, they remove important nutrients from the soil that are necessary for development. Adding fertilizer will help replace elements like nitrogen and phosphorus to aid in growth and yield. There are many methods of fertilizing and many types of fertilizers out there so you have a number of options to achieve the desired results.
The two basic categories of fertilizer are organic and conventional (synthetic) fertilizer. Both methods will work but there are some pros and cons to consider for each. The major reason to choose an organic vegetable fertilizer is to build up your soil for the long haul. Organic fertilizers do not result in salt buildup in the soil and run a significantly lower risk of causing fertilizer burn on plants. The main disadvantage is that organic fertilizers often come with a higher price tag, and because they tend to dissipate more quickly once applied, may need to be applied more frequently. A conventional fertilizer, by contrast, may cause salts to build up in soil over time. However, many conventional fertilizers are less expensive than organics and are formulated to be slow-release, meaning one application can feed plants over a much longer time period than an organic fertilizer. As always, it is important to do some product research and read the instructions carefully before use. Consult one of our experts if you have doubts on how to use the product.
Please keep in mind that adding nutrients that are not needed can result in deficiencies of other nutrients and can damage your plants. For this reason, over fertilizing can be worse than not adding enough. The only real way to judge your soil’s needs is to have a soil analysis completed. Locally, the CSU soil lab will do an analysis for a small fee and you can pick up a free testing kit here at Fort Collins Nursery.
Now that you put in the time and effort to plant your garden, don’t forget to give your plants the additional support they need to thrive through the summer. Support structures such as garden stakes, trellises and cages encourage a healthier crop and provide many benefits to the plants like proper air circulation and additional sunlight.
For some basic rules and tips on supporting specific plants, check out this link from Burpee.
Looking for some late-summer, early autumn perennial bloomers? Add a colorful chrysanthemum to your flower bed or fall container garden! Fort Collins Nursery offers hundreds of these prolific, hardy and beautifully bushy perennials.
Mums come in a wide variety of colors, from yellow, pink, magenta, red, lavender, and more. Blooms on mums typically last for weeks providing a late-summer boost when other flowers have given out.
Fort Collins Nursery also offers a great selection of colorful asters, also a hardy late-summer and autumn bloomer. Small, abundant, star-shaped flowers tower on 2-3 foot plants, providing a nice backdrop in perennial beds.
Both mums and asters appreciate full sun, and a good dose of compost when planted. They also prefer to be watered at their base. Watering from above, onto the leaves, can encourage powdery mildew.
Pumpkins, with their edible flesh and long storage life are a warm season crop. They require a long growing season of nearly 85 days, so it’s best to start them indoors from seed. About a week after the last frost (on average May 15 along the northern Colorado front range), pumpkins can be planted outdoors. But be careful, pumpkins do not like their roots disturbed. We recommend starting them in a natural peat-pot (offered in the garden shop) that can be planted directly in the soil.
Choose an area in your garden or yard that receives plenty of sunlight, and has at least 8 ft. x 8 ft. for pumpkin vines to spread. Soil should be rich with organic matter, but not over-fertilized, which can stunt fruit growth.
Pumpkins will start to develop after blossoms are pollinated, so encourage pollinators to visit your garden with other flowering plants. Also avoid using pesticides in and around your garden, since also harm beneficial insects as well as pests.
To increase the size of giant pumpkins, pick a few nice-sized fruits and cut back the vine just beyond them. This will help all the resources of the plant to be devoted to the growth of those remaining pumpkins.
Interested in entering our annual Giant Pumpkin Contest? See our Calendar of Events and check the month of October for the exact date. Get growing!
PlantTalk Colorado – Growing Great Pumpkins
Rocky Mountain Giant Vegetable Growers
Old Farmer’s Almanac: Pumpkins
You Tube: Larry Checkon, the world record holder for the largest pumpkin
Nothing smells as inviting as fresh garlic sautéing in a pan. These tasty bulbs can be added to nearly any style of cuisine, or even roasted and eaten by themselves.
Fall is the time to plant garlic for next year’s harvest! This over-wintering bulb needs at least four to six weeks to establish itself. Plant garlic cloves about 12 inches apart in loose, amended soil with plenty of organic matter. Garlic will do best if planted when soil temperatures are 40°F, but before the ground freezes.
Each garlic clove will produce a bulb in the summer. After the leaves have turned brown, garlic is ready to be harvested. Harvest is easiest with a digging fork to loosen the soil without disturbing or damaging bulbs. Drying garlic, or curing, can help your harvest last for up to a year. The biggest and healthiest cloves can be replanted again in the fall.
Keep soil moist but not too wet, which will rot garlic bulbs. Make sure to keep the beds free of weeds, which competes too much with the bulbs.
Fort Collins Nursery has garlic varieties arriving in September, but they don’t last long! Stop in and get planting!
One of the most popular additions to any vegetable garden is homegrown tomatoes. Nothing beats the taste of a juicy, sweet tomato that has ripened on the vine.
At Fort Collins Nursery, we offer a huge variety of tomato plants and seeds to satisfy your hankering. Our varieties include: Beefsteak, Cherry, Roma, Brandywine, Lemon Boy, and more! Call us at 970-482-1984 for availability.
Tomatoes are tender plants. We recommend using a Season Extender or Hot Kap to protect against cold temperatures. We also offer frost cloth.
Don’t forget to keep tomatoes off the ground with a sturdy tomato cage, garden stake, tomato tower, or even try a Topsy Turvy, and hang them upside down! Whiskey barrels also make excellent containers for indeterminate tomato plants – they’ll just grow and grow!
Did you know tomato plants like salty soils?
Sunflowers are not only an attractive flower, they also have rich history providing edible seed crops. Sunflowers do best when planted directly in the soil, after night temperatures warm to above 50 degrees. As their name suggests, need plenty of sunlight (minimum of 6 hours per day). They will also turn their flower heads to follow the sun from east to west.
For giant sunflowers, make sure to chose an area in the yard near a fence or support structure. Sunflowers tend to become very top-heavy as seeds develop, sometimes pulling themselves over (credit anna). Watering sunflowers deeply but infrequently encourages deep root development (which will also help them stand upright). Sunflowers can also be utilized for shade and structure for other vegetables in the garden.
In order to keep birds and squirrels from helping themselves to sunflower seeds, paper bags, nylon mesh or nets can be placed over the flower heads. The best bet is to plant a few extra for wildlife to enjoy, and you to enjoy watching them.
Sunflowers tend to attract aphids, which will feed on the plant and cause some stunting. Instead of using a pesticide, which can harm beneficial insects such as bees and butterflies, try spraying aphids off with a jet of water.