Winter Tips

Spider mites love dry indoor conditions

Colorado winters are often a very dry time of year, both inside and out. This warm, dry indoor climate is an optimal condition for spider mites, a common plant pest.

Spider mites are small, and difficult to spot. Inspect your houseplants for small flecks of discoloration and leaf loss. They also produce areas of webbing, which are easier to see. Bring in a sample of your troubled plant, and a Greenhouse representative can help diagnose it.

The best prevention for spider mites is proper watering. Raising the humidity level for houseplants creates an unfriendly environment for mites. Spraying webbed areas with a jet of water can also help. Try grouping houseplants together, or introducing a humidifier. If these methods do not work, contact us for insecticide recommendations.

Tis the season … for fungus gnats

Have you noticed an annoying visitor that you haven’t been able to get rid of? We’re not talking about a relative that’s overstayed their holiday welcome … we’re talking fungus gnats. These small black flies live and breed in the soil of houseplants.

With each watering, more gnats are given a warm, moist incubator for nearly 200 eggs in their 10-day lifespan. In order to get rid of fungus gnat larvae, allow houseplant soil to dry out between waterings. If needed, repot with fresh potting soil, which offers less degraded material for gnat larvae to snack on.

If the infestation is particularly bad, Fertilome offers an Indoor/Outdoor Multi Purpose Insect Spray that works when applied to the soil. A Sticky Whitefly Trap also works to capture gnats, but only controls the flying adults

Christmas tree care

Deck your halls with a fresh cut Lodgepole pine, Scotch pine, Alpine fir or Fraser fir from Fort Collins Nursery! You can keep your tree fresh with a little care.

When you get your tree home, cut about an inch off the trunk, and immediately place the trunk in a reservoir of water. Keep this reservoir full, and check every day or so. We also recommend a homemade preservative solution of 1 gallon warm water, 1 cup light syrup and 1/4 cup bleach. This solution will help keep mold at bay, feed the tree and replenish moisture.

Add a dose of prevention from wilting Christmas trees, evergreen wreaths or garland with a protective coating of Wilt Pruf Plant Protector. This unique spray coats needles to prevent moisture loss, keeping evergreens lasting longer and less needle loss. Wilt Pruf also works year-round on plants stressed by drought, windburn and transplant shock.

Short days, grow lights

If you noticed a slight sluggishness in your routine when the days begin to get noticeably shorter, imagine what your sun-loving tropical houseplants are feeling!

Houseplants will lose their leaves and grow small, thin leaves in their place when plagued by low-light conditions. Using regular florescent or incandescent bulbs do not typically replace the color spectrum of natural sunshine.

A grow light like Indoor Sunshine can be used in standard incandescent light fixtures, but provide balanced, full color spectrum light. These bulbs last longer and are energy efficient. Not only will your plants feel better, you may, too!

Winter herb gardening

Indoor herb gardens are a great way to extend the growing season and spice up culinary dishes. Choosing individual pots for herbs help control the moisture needs of particular plants. Most herbs like to be well watered, but also have good drainage. We recommend using an organic fertilizer high in nitrogen, such as Age Old Grow liquid fertilizer or Grow More Herb Food. Also, follow these tips for growing and harvesting your herbs:

  • Rosemary grows best from a nursery starter plant. This Mediterranean herb appreciates very good drainage, and allowing the soil dry between waterings. Harvest Rosemary continuously as long as the plant is growing. Container plants can grow 1 to 3 feet tall.
  • Parsley is an excellent addition to most recipes, it’s rich in vitamins A and C and minerals calcium and iron. You can plant parsley from seed, and harvest as soon as it is well established. Snip individual stems from the plant and it will produce new growth.
  • Oregano is best harvested once it reaches 8 inches tall. Frequent harvests produce a bushier plant. Oregano has a very strong flavor when fresh, add a little at a time to taste.

Do voles dig your landscape?

If you’ve found damaged plants, mounded soil, and small burrow holes, you may have an unwelcome rodent helping themselves to your garden. Voles, which resemble large mice, are common in Northern Colorado foothills, forests and prairies.

Voles live as families in burrow systems and can cause extensive damage to trees,  shrubs and crops (especially root vegetables). Some evidence of vole damage can include girdling of the bark of trees and shrubs, but underground root damage may not be seen.

Most damage is caused in winter months, so late fall is a great time to apply Molemax repellent. This product also repels moles, skunks, rabbits and other burrowing animals and is safe to use around children and pets.

Prevent damage to lawn from Snow Mold

As heavy winter snow melts away, you may discover large patches of your lawn that are matted down and appear straw-colored or gray. This is caused by gray snow mold, a fungus.

Cause of Snow Mold

Snow Mold occurs when snow or leaves cover lawns for a prolonged period through the winter, especially in shady areas. The mold forms a circular shape, and actively grows when temperatures are just above freezing. Heavy snow cover can actually insulate the ground and keep it from freezing, creating the perfect conditions for this fungus to thrive.

Snow Mold does not thrive in dry warm conditions, and typically the worst symptoms are that the affected patches will take slightly longer to green up in the spring than unaffected areas. Typical front range winters to not lend themselves to the growth of Snow Mold, as we rarely have heavy snow cover over extended periods of time. However, the occasional years when we do see a heavy blanket of snow that doesn’t quickly melt off lead to widespread Snow Mold in people’s lawns.

Treatment of Snow Mold

Chemical treatments are not recommended for the treatment of a lawn already affected by Snow Mold. To help your lawn recuperate for spring, gently rake the affected areas to knock away dead leaves and fluff up matted areas. This will help increase air flow and reduce the conditions that are favorable to mold growth. Do not power rake affected grass, as this can risk damaging and possibly destroying the already traumatized plants.

Prevention of Snow Mold

The best cure for Snow Mold is prevention. Thatch management is an important key in Snow Mold prevention. Practice core aeration of your lawn at least once a year to keep thatch levels below 1/2″. Another important factor is mowing the grass short before winter. Cut the lawn to 1-1/2 to 2” at the last mowing. This should be a gradual process and not a one-time exercise. Lower the height a notch a week until the mower is set at 1-1/2 to 2”. Remove leaves and matted materials from the lawn in the fall, which encourages proper air flow. Avoid heavy applications of nitrogen in the fall, as this can cause grass to push out new growth late in the season, adding to matting problems.

If Snow Mold is a consistent problem over several years, applying a fungicide, like F-Stop from Fertilome, in the fall can prevent damage. However, it should be noted that this is only effective as a preventative measure and should only be done when severe and repeated cases of Snow Mold have taken place.

Houseplant pest control and care

SpiderMitesAfter a brief summer vacation outdoors, houseplants come back inside for a comfortable winter. Some may return with unwelcome visitors, such as fungus gnats, whiteflies, mealybugs, scales, aphids or spider mites.

Allowing soil to dry between waterings helps discourage egg-laying of pests in soil mixes, as does repotting. Wash pests off leaves with a quick spray of water or, if necessary, a pesticide treatment.

Also, remove dead plant material and leaves, since they harbor larvae.

If the problem persists, bring a sample of the pest in and ask one of our knowledgeable greenhouse staff for a recommended treatment.

Wrap trees to protect from sun scald

Bright, cold days of winter can cause sunscald on thin-barked woody plants such as willows, aspen, mountain ash and maple.

The warmth of the sun heats the bark, essentially waking it from a dormancy. The sudden drop in night temperatures then kills the active bark. Bark will show signs of damage by turning color, splitting or shedding bark.

Protect your thin-barked trees with tree wrap in October or November, but be careful to remove it by April.

Protect trees from heavy snow

All trees can be damaged by heavy, wet snow when still in full leaf. Trees that grow quickly, such as poplars, elms and willows, with deep v-shaped crotches also tend to be more brittle and prone to breakage.

Evergreens are especially susceptible since they never lose their full foliage. Protection of these types of trees starts with good tree selection and proper pruning.

Conical formed trees such as conifers withstand heavier snow loads, as well as deciduous with less branch area.

Always check your trees during snowstorms ­‑ a few gentle shakes to remove snow can go a long way to preserve drooping branches.