Extending Your Tomatoes at the End of the Season

Photo taken October 25, 2014 by E.J. Bennet

We’ve had several Master Gardeners in the past few years give us tips on extending and preserving the last crops of tomatoes. Their advice is still sound and worth trying. Thanks to E.J. Bennet, Joyce D’Agostino, and Carol King.

Speed Ripening

If you want to maximize your tomato output through the first frost, follow these steps in late August or early September to speed-ripen them on the vine:

Use Caution with De-Icing Salts

De-icing salt applicator, photo courtesy overstock.com

Winter is in full swing in Jefferson County! Even though it's been a warm winter, snow and ice are inevitable. In addition to shoveling all that snow, many people also apply de-icing salts to make the walkways safe and passable. While these products can certainly help ensure safe footing in treacherous conditions, they can also damage the landscape plantings that they contact. So – what to do? Protect your footing or protect your plants? It’s possible to do both.

January Word of the Month: Winter Quiescence

Photo courtesy Donna Duffy

Have you ever wondered what's going on with your tree roots underneath all that winter snow? Michael Snyder, Chittenden (Vermont) County Forester, explains the concept of winter quiescence - a state in which tree roots are resting, but ready.

It's Frost Season! But What Kind of Frost is That?

Autumn frost, photo by Donna Duffy

It’s the time of year when frost occurs almost daily. But what kind of frost is it? Just a few degrees or a slight change to the environment can separate air frost from ground frost, or hoar frost from glaze or rime. Following is a detailed look at what each term means, courtesy of The Weather Channel.

Hoar frost, photo by Donna Duffy

Hoar frost

Consisting of tiny ice crystals, hoar frost is formed through the same process as dew - but only when surface temperatures are below freezing point. 

Hoar frost follows a feather-like appearance, forming when the surface temperature reaches 0C before the dew begins to manifest on it.  Often more rounded frost particles appear, called 'white' frost, which is when the dew forms first and then freezes as a result. However, if there is any fog present, this usually prevents the formation of hoar frost since it lessens the potential for the cooling of the Earth's surface.

Air frost

Air frost happens when the temperature of the air plunges to or below the freezing point of water. The depth of air above the ground also must have increased to at least three feet above the ground. The combination then creates a layer of cold air hovering just above the ground that should hit 32F or below, and gradually becomes thicker and thicker as more heat energy fades away and the temperature continues to fall.

Grass frost

A grass frost is an un-official strain of ground frost. A grass frost takes place when natural surfaces, such as grass, freeze, while other surfaces such as tarmac and concrete pavements don’t. The reason why such man-made surfaces don't come into contact with this frost is due to their better ability to hold onto warmth.

Glaze or rime

Frost is often confused with rime or glaze. Rime is a rough white ice deposit which forms on vertical surfaces exposed to the wind. It is formed by supercooled water droplets of fog freezing on contact with a surface it drifts past. Glaze can only form when supercooled rain or drizzle comes into contact with the ground, or non-supercooled liquid may produce glaze if the ground is well below 32F. Glaze is a clear ice deposit that can be mistaken for a wet surface and can be highly dangerous. On the roads, we often refer to glaze as “black ice”.

Glaze, also called black ice, photo courtesy science.howstuffworks

Ground frost

Ground frost relates to ice formed on the ground, or on objects and trees, where the surface consists of a temperature below freezing point. On those occasions when the ground cools faster than the air, ground frost can occur without an air frost.

So there you have it! Everything you always wanted to know about frost!\

Crocus already? Too early?

Crocus leaves in Lakewood, 1/17/18

It’s early February and some crocus are already emerging. In fact, crocus leaves appeared in my yard in mid-January. What’s going on?

An early bloom certainly isn’t unprecedented in Denver and Jefferson County. The National Phenology Network (NPN) collects reports on the status of plants around the country and combines them with weather data to create models of where spring has sprung. Just last year, data from the NPN indicated that Denver’s plants were blooming up to three weeks ahead of the average for 1981-2010.

What are “Chill Hours” (and why is this important to my fruit trees?) By Joyce D’Agostino

Golden Delicious Apples, photo courtesy Stark Bro's Nursery

If you have fruit trees in your landscape, you may have noticed that some years the trees seem to produce abundantly, other years there is less of a crop. This can be puzzling to figure out why some years are considered a ‘good fruit year’, and others are not.

Nature's Beauty: Hoarfrost by Donna Duffy

Photo courtesy Colleen Hart, The Weather Channel Facebook Page

Sometime this winter, you may be fortunate enough to see hoarfrost in your landscape. But look quickly, because it will disappear with sunlight.

According to the Old English dictionary (c. 1290), hoarfrost is defined as "expressing the resemblance of white feathers of frost to an old man's beard." No, this isn’t frost on performance-enhancing drugs, but it can be quite different from your normal frost! Colleen Hart of The Weather Channel provides the following facts about hoarfrost.