Heat Mats for Indoor Seed Germination by Brenda Sterns

Photo:Suncore

As March brings 50-60°F warm days combined with all the winter snows, our yards are showing slight signs of life. For many of us, this tinge of greenness ushers forth images of what our 2024 gardens will hold.  What will we grow – vegetables, annuals, perennials?   We know the last frost date is two months away and now is the time to start seeds indoors.  As you eagerly grab your seeds, pots, and soil to start your best garden ever, take a moment to think about heat mats.

Summer Vacation for Houseplants; Tips for Moving Them Outside by Rebecca Anderson

Oxalis Plant photo by Rebecca Anderson

Many houseplants will get a boost from being outdoors during the warm summer months. Increased sunlight exposure will let them recover from the low light levels inside most homes. Since most houseplant originate from tropical areas, they should not be moved outdoors until night time temperatures are above 55 degrees. Place them in an area with partial shade and good wind protection. Ideal locations would include a covered porch or under a tree. After a few days, sun-loving plants such as jade (Crassula ovata), poinsettia (Euphorbia pulcherrima) and hibiscus (Hibiscus sp.) can be moved to a full-sun location. Christmas cactus (Schlumbergera sp.), umbrella trees (Schefflera arboticola) and citrus plants prefer to stay in the shade. Exposing a houseplant to excessive sun before it has been hardened off will cause photo oxidization, or a yellowing of the leaves. This process is the plant version of a sunburn. 

Care for African Violets by Vicky Spelman

Photo Elaine Lockey

African violets can be a great indoor plant for Colorado. Their care is fairly simple and they will bless you with beautiful blooms. Here are tips for their care:

• Light: Moderate to bright, indirect, indoor light.
• Water: In general, African Violets need just enough water to keep the soil moist, but never soggy and should be room temperature. They have self-watering pots - a smaller pot with the violet sits in a larger pot that has a water fill line and when nearly empty refill.
• Fertilizer: Your fertilization practices can also impact how well African violets bloom. Unlike plants that grow outdoors, houseplants are totally dependent on the grower to apply sufficient nutrients without overdoing it. The small pots these plants are typically grown in do not maintain a large reserve of nutrients. If you do not fertilize them on a regular basis, they may not have the necessary nutrients to spend on flowers. On the other hand, too much fertilizer with high nitrogen content can lead to lush foliage at the expense of flowers.
• Other tips: Pinch off spent blossoms and blossom stems to encourage development of new blooms. Place plants away from floor vents, fans, or entrance doors to avoid air drafts and bursts of cold air.

For additional information: 

African Violet http://planttalk.colostate.edu/topics/houseplants/1301-african-violet/

Why Isn’t my African Violet Blooming. https://extension.psu.edu/why-isn-t-my-african-violet-flowering.

Low Humidity in House Plants by Carol King

Plants on Pebble Tray. Photo the-news.co

This time of year, Colorado gardeners turn to indoor plants to soothe our gardening souls.  However the indoor environment in our homes can be very harsh for many plants. Many house plants are native to humid, tropical rain forests and require special consideration when they reside in Colorado homes. While lighting and temperatures need to be monitored for successful indoor gardening, humidity is the big issue during colder months.  Heating systems common in Colorado circulate dry, warm air throughout the house. Our indoor environment often has less than 10 percent humidity. This is a drastic reduction from the 70 to 90 percent relative humidity levels found in the native climates of most tropical plants.

Why does this matter? Humidity is the level of moisture in the air and can affect a plant's need for water.  Plants grown indoors with low humidity lose more water through transpiration, so their root systems require more water. In addition, plants located near heating or cooling vents may develop leaf spots or brown tips.

Here are a few tips to help alleviate low humidity problems:

• Misting plants may help alleviate this condition, however, it must be done frequently to be effective, and it may promote some foliar diseases. 
• Place several plants together on a tray filled with gravel. Filling the tray with water provides the humidity many plants need. Make sure the bottom of the container does not stand in water; the soil will become water-logged and cause root damage. 
• Use a humidifier around your plants. 
• For house plants with moderate humidity needs, group them together during the heating season. Each plant gives off humidity through transpiration. Clusters of plants will create very good humidity in the surrounding air.

For more information see this:  http://planttalk.colostate.edu/topics/houseplants/1317-houseplants-temperature-humidity/

Rosemary “for Remembrance” By Olivia Tracy

Rosemary (Rosmarinus officinalis); photo courtesy of PlantTalk Colorado

During Shakespeare’s time, rosemary (Rosmarinus officinalis) was often associated with memory or remembering; it was given as a sign of friendship, and the early Herballs believed that the scent could “quicken the senses and memorie” (John Gerard, The Herball, Or Generall Historie of Plantes, 1597). These herbals may have been on to something-- recently, scientists have found possible relationships between the scent of rosemary and improved cognition.⁴

Today, rosemary is a welcome presence (and scent) in an indoor winter herb-garden. A Mediterranean plant, rosemary doesn’t tolerate low temperatures well; however, when planted in a container, you can keep it indoors during the winter, and move it outdoors during the warm summer months.² You can buy rosemary plants from a store, or you can start them from seed. (You can also propagate rosemary through cuttings; however, it is best to take cuttings from rosemary in the spring or summer.)³ 

• Plant your rosemary plant in soilless mix (potting soil),² and be sure to allow the soil to dry between watering (rosemary is a fairly drought-tolerant herb).¹ 
• Apply water-soluble fertilizer every few weeks to help the plant thrive in the indoor space.² 
• Like most herbs, rosemary loves sunlight, so be sure to place your rosemary plant in an area that will receive the largest amount of possible sunlight (in a south- or west-facing window).² 

If you’d like more information about rosemary, other herbs, and herb gardening, the following webpages were sources for this post, and are excellent sources to explore: 

¹CMG GardenNotes #731, Herb Gardening http://www.ext.colostate.edu/mg/Gardennotes/731.pdf , 

² PlantTalk 1056- Indoor Herb Garden http://planttalk.colostate.edu/topics/annuals-perennials/1056-indoor-herb-garden/

³If you hope to propagate rosemary or other herbs by cuttings, you may find useful advice in this article by the Missouri State Extension: https://extension2.missouri.edu/g6470 

⁴Recent study exploring the relationship between the scent of rosemary and cognition in schoolchildren: http://www.scirp.org/journal/PaperInformation.aspx?paperID=79934 

Easy Houseplants for Your Indoor Garden

January in Colorado is a tough time to be a gardener in Colorado. Having a collection of indoor plants is one way to assuage our desire to be in the garden. Dry furnace air and lack of sunshine makes indoor gardening a challenge along the Front Range. Organic Life Magazine suggests eight very simple to grow house plants.

Forgetful plant parents should have no problem with these tough varieties. https://t.co/ddh2cYU3oT

— Organic Life (@OrganicLifeMag) January 1, 2018

Brighten Your Space with Indoor Citrus By Olivia Tracy

Etrog Citron (Citrus medica); photo courtesy of Olivia Tracy

This winter, if you’re hoping to cheer up your indoor space, why not incorporate the bright color and invigorating scent of a citrus tree? While some citrus varieties are too large to grow indoors, there are dwarf cultivars of lime, lemon, orange and tangerine that can grow in containers, including the ancient Etrog Citron (Citrus medica; pictured); sour citrus does particularly well, as it requires less heat to ripen.³ While many nurseries are now closed for the season, you can still mail-order dwarf citrus trees from reputable seed and plant distributors. 

Some Indoor Citrus Varieties Include:^1,2,3 

LIMES: 

Bearss Lime (Citrus latifolia)

Kaffir Lime (Citrus hystrix), grown mostly for the leaves

LEMONS:

Meyer lemon (Citrus x meyeri)

Variegated Pink Lemon (Citrus x limon)

TANGERINES AND ORANGES: 

Mandarin/Satsuma Oranges (Citrus reticulata); actually a tangerine, with fragrant flowers and the familiar ‘orange.’

Calamondin Orange (Citrofortunella mitis), a small, sour orange; often grown as an ornamental.

Forcing Paperwhite Narcissus Bulbs by Carol King

Photo brighter blooms.com

Paperwhite narcissus are classic holiday flowers that display the spirit of Christmas. They are available to purchase everywhere during this season. Classical mythology states that a young man named Narcissus was vainly staring at his own reflection in a pond and he fell in and drowned, then legend says that the first narcissus plant came up where he had lost his life. They’re sold this time of year to give us something pretty to grow during the darkness of winter. 

Planttalk Colorado has this advice for planting these lovely bulbs:

"Paperwhite narcissus (Narcissus papyraceus) are one of the easiest bulbs to force for cut flowers or ornamental displays in the home from December to March. They are a form of daffodil that can be forced without a chilling period.To force paperwhites, fill a bulb pan with about one to two inches of potting soil, then position the bulbs in the soil so they are nearly touching each other with pointed end up. Add enough potting soil so that only the top half of the bulbs remain exposed, then water well.

History of the Irish Shamrock by Carol King

Photo courtesy CSU

The Irish shamrock (Irish: seamrog) is the most recognized symbol of the Irish. It has been symbolic of many things through the years. It was considered to be a sacred plant to the Druids of Ireland because its leaves formed a triad, and three is a mystical number in Celtic religion as well as many other religions. Supposedly, St. Patrick used it to illustrate the Holy Trinity to help convert Irish peoples to Christianity. 

In Ireland, all shamrocks are considered lucky and are worn and given as gifts on St. Patrick's Day. However, there is some disagreement among the Irish as to the exact plant, but most Irish growers will tell you that Trifolium repens, White Clover, is the plant most commonly known as a shamrock.   What we consider to be a common lawn weed, is a native of Ireland.  In Colorado, this Irish shamrock grows in our lawns, in prairies, pastures and foothills. If you enjoy clover honey, you can thank this lovely little plant.

Pamper Your Poinsettias! by Donna Duffy

Photo CSU Co-Horts

Many of us will adorn our homes with poinsettias this holiday season. You’ll have several colors (pink, white, variegated, even hand painted) to choose from in addition to the traditional deep red. Regardless of color, look for dark green foliage, and richly colored bracts (the modified, colorful leaves). Poinsettias are tender plants, and will drop their leaves very quickly if chilled. Be sure to protect the plant with a plastic sleeve as you leave the store or nursery.

Follow these tips to keep your poinsettia healthy and colorful.

Light: Find a location with very bright, indirect light. Don’t put it in a hot, sunny window.

Water: Apply water thoroughly whenever the pot feels light, or the soil is dry to the touch. If the leaves are wilting, water immediately. If your plant came in a basket, discard any standing water. If it is wrapped in foil, cut a hole in the bottom and put a saucer under the pot.

Fertilizer: Use an all-purpose indoor plant fertilizer until the poinsettia is in full color, then cut back and fertilize at ½ strength every third or fourth watering.

Temperature: Poinsettias don’t like cold, but they will appreciate a cool room (60-70°). Avoid hot or cold drafts from heaters, fans, fireplaces or ventilating ducts.

Poinsettias are native to Mexico and Central America. They came to the U.S. by way of our first ambassador to Mexico, Joel Robert Poinsett in 1825. Contrary to popular belief, the poinsettia is not poisonous. Even so, they should be kept out of reach of pets and small children.

For more information check this Poinsettia Fact Sheet.

Why Fresh Flowers on Valentine's Day? by Carol King

Photo sodahead.com

Legends and lore abound on why we celebrate Valentine’s day by giving flowers to our loved ones.  Here’s one of my favorites. This one involves the lore of forbidden love and has been favored over other stories by hopeless romantics.

Emperor Claudius II issued an edict forbidding marriage because he felt that married men did not make good, loyal soldiers to fight in his army. They were weak because of the attachment to their wives and family. St. Valentine was a priest who defied Claudius and married couples secretly because he believed so deeply in love. Valentine was found out, put in prison, and later executed.

The law of irony then came into play, as St. Valentine fell in love with the daughter of the Emperor. Prior to his beheading, St. Valentine handed the lady a written note and a single red rose - the very first valentine and the very first fresh flower.  From this, the gifting of flowers for Valentine's day began.

Photo proflowers.com

If you receive a gift of fresh flowers from your valentine, here are some tips to make the sentiment last longer.

Cut flowers
Cut the stems of boxed flowers, such as roses or carnations, under water.  Remove leaves and foliage that would be under water. Place the flowers in warm water with a floral preservative added.  Keep flowers in a cool spot away from the sun. Add water every day and every fourth day, change the water completely.

Spring bulbs
Colorful containers of tulips, hyacinths, daffodils and crocus are popular Valentine's Day gifts.  Keep them as cool as practical to prolong bloom. Water when soil dries out.

Azaleas
Red, pink and white flowers make azaleas a natural Valentine's Day gift. Under diffused sunlight and with frequent waterings, the showy blooms can remain in good condition for several weeks if they are kept at 55 to 60 degrees. Never let your gift azalea totally dry out. Because they are woody plants, azaleas can be kept growing from year to year, but getting them to bloom again can be tricky.

Photo paceseeds.com

Calceolarias and cinerarias
These are popular gift plants because of their vibrant colors. The former also is known as pocketbook plant, because it has pouch-like blooms resembling a purse. Blooms will last longer if you keep the plants at 50 to 60 degrees and if you water frequently.  Water when the soil surface just begins to feel dry.
Here is complete information on keeping Valentine flowers fresh.


Valentine lore Article Source: http://EzineArticles.com/3973848

Low Humidity Problems and Indoor Houseplants by Carol King

Spider Plant Chlorophytum comosum

This time of year, we Colorado gardeners turn to indoor plants to soothe our gardening souls.  However the indoor environment in our homes can be very harsh for many plants. Many of our house plants are native to humid, tropical rain forests and require special consideration when they reside in our Colorado homes. While lighting and temperatures need to be monitored for successful indoor gardening, humidity is the big issue during colder months.  Heating systems common in Colorado circulate dry, warm air throughout the house. Our indoor environment often has less than 10 percent humidity. This is a drastic reduction from the 70 to 90 percent relative humidity levels found in the native climates of most tropical plants.

Why does this matter? Humidity is the level of moisture in the air and can affect a plant's need for water.  Plants grown indoors with low humidity lose more water through transpiration, so their root systems require more water. In addition, plants located near heating or cooling vents may develop leaf spots or brown tips.

Norfolk Island Pine Care by Planttalk Colorado

Photo courtesy squidoo.com

Norfolk Island pine is a tropical evergreen tree that is adaptable to indoor conditions and is a favorite of many indoor plant enthusiasts. Often used as an indoor Christmas tree, It is not a true pine. In the landscape, it can grow up to 220 feet tall with a trunk as large as 10 feet across. Small trees grown indoors are uniform in appearance and have branches that are parallel to the ground. The Norfolk Island pine is a long-lasting houseplant that grows three to six inches annually.

Poinsettia Care by Carol King

Photo Lowes.com

With proper care, the poinsettias that decorate your home during the Christmas season can retain their beauty for many weeks.

Follow these steps for best results:

Photo CSU

• Choose plants with deep, dark green foliage and full, undamaged colored leaves, also called bracts. The actual flower is yellow and is located at the base of the bracts. Plants with tightly-closed flowers that have not yet shed pollen will last the longest in your home.

• Place plants in the sunniest part of the home to ensure proper growth. Avoid placing a poinsettia near cold drafts, radiators and heat vents. To keep the color of the bracts bright, maintain your poinsettia between 50 and 70 degrees Fahrenheit. Cooler temperature prolongs bract color, but don't allow it to dip below 50 degrees.

• Water poinsettias thoroughly as needed. If your poinsettia is wrapped in a decorative foil, punch holes in the bottom of the foil to ensure proper drainage and removal of excess water.

Contrary to popular belief, the flowers and leaves of poinsettia plants aren't poisonous, nor are they edible.     Here’s a great web site for “All Things Poinsettia” .

(Poinsettia care information from Planttalk Colorado.)

Moving Houseplants Indoors by Sharon Routa

What to do now!  No more daily watering or constant deadheading.

One of the projects I’ll be doing this fall is moving house plants indoors.  Before I move them back indoors, I put them in a shadier part of the yard.   This helps them make an easier adjustment to the change in light and environment they are going to undergo.

I cut them back, getting rid of damaged growth; this also helps to control the size of plant, and encourages new growth.  Fertilize one last time before you bring plants into the house.  Do all of this before the weather turns cool or they may go into shock.  One symptom of shock is leaf drop.  Plants will usually survive this with regular watering.   It’s difficult for plants to deal with changes in light and temperature.  Check the foliage and soil thoroughly for pests before you bring them indoors.  If an insecticide is needed, read the label carefully before applying.  Be certain you check the drainage holes on containers for slugs or bugs, which you can manually remove. 

African violets –not just foliage plants! by Elaine Lockey

It seems that you either have luck with African violets blooming or you don’t. I was in the no-luck category for many years. I had one particular African violet for more than 5 years with one tiny little flower the entire time. I guess I was keeping it for the cute fuzzy foliage as I’d given up on flowers. What was the secret of my non-gardener friends who could produce gorgeous blossoms on theirs?

Fruit Flies and Fungus Gnats by Carol King

Have you noticed  little black bugs flying around your house this winter? You probably have either have fungus gnats or fruit flies.  You need to look at your particular situation.  Did you get a new plant for Christmas?  Probably fungus gnats; check the plant soil. Did you just start to compost your garbage or receive a fruit basket?  Probably fruit flies; check the compost collector. Neither one of these are harmful so if you don’t mind gnats buzzing your head (a la B.O. Plenty) just ignore them.

Houseplant Moving Day by Elaine Lockey

“Brrrrr” says my peace lily, “How do I look in this wool hat?” says my aloe.  Okay okay, I get the hint.  With temperatures dipping down into the 40’s at night our lovely tropical houseplants are ready to move to a warmer climate, that being your house.  Leaving them out too long in the cold will damage them and eventually kill them.
There is a bit of prep that you’ll want to do to get ready for your returning houseguests.  The first thing you’ll want to plan out is space. Chances are you’ve filled in the all the spots that your plants normally take with furniture or other décor.  Time to reshuffle the room and provide inviting spots that will give your plants plenty of sunlight.  Maximize space by using plant stands with multiple levels.  Get creative, plants can look good in any room of your house as long as it offers the amount of light levels that the plant needs. Plants like Sansevieria and pothos can handle lower light levels and can take up spots further into the room allowing plants like aloes and bromeliads the strongest light.

Indoor Winter Gardening

Garden Girl shows us how to create an indoor winter garden in a 6X14 foot area!

Picking a Poinsettia

There is more to picking a poinsettia than just going in the store and buying one you like.

Dr. Steven Newman, Greenhouse Crops Extension Specialist and Professor of Floriculture at Colorado State University who is a specialist in poinsettias gives this advice:

Picking a poinsettia « Gardening after five