It's thrilling to see spring arriving in Fort Collins. Many bulbs are coming up and blooming, trees are budding out, and gardens everywhere are waking up. If you're like me, you can hardly wait to get outside and get busy in the garden! Spring can also be fickle, however, and there are days when the temperature or the weather keeps you indoors. You can make a list of things you'd like to be doing, but you'd much rather be doing something, right? You can! You can start tuberous begonias now in pots for summer-long bloom.

Tuberous begonias are large-flowered annuals that grow in filtered shade. They especially love early morning sun but will do well under an awning or under lattice work. The plants have large rose-like flowers in bright colors, sometimes with bi-colors and ruffled edges. The foliage is thick, hairy and luxurious, but also fragile. For this reason, a protected area is necessary for these beauties; they will not tolerate windy conditions. Upright and trailing varieties are available. Upright begonias will have larger flowers while the trailers will bloom more profusely. Trailing varieties make lovely hanging baskets.

To start your begonias, you'll need to purchase the tubers from a local nursery or garden center. The tubers look like flattened potatoes with rounded bottoms. They will come packed in a sawdust-like material. You'll also need a container with good drainage and at least 6 inches in diameter for each begonia. Clay pots work well, but you can use something more decorative or a hanging basket container. Choose your container carefully because you will not want to disturb the tuber once it has been planted. Next, choose a good light potting mix medium and fill the container, packing down lightly, to within an inch and a half of the top of the container. Then gently unpack and inspect the begonia tuber. On the rounded side (bottom) of the tuber, you will see some hair-like roots, and on the top side there may be a depression with tiny pink sprouts. Avoid touching the sprouted areas and plant, rounded (root) side down in the center of the growing medium. Gently cover with about a half inch more potting mix, making sure you cover the tuber completely.

Place the container in a well-lighted area and water. Keep the soil lightly moist but not soggy. If you are unsure about watering, it's best to wait a day. Once or twice a week watering is all that is required. Bright light, not direct sun is best and a north window is generally very suitable. In about 3-4 weeks you should see small pink sprouts emerge. You are now on your way to beautiful summer color with tuberous begonias! Continue to water your begonias and enjoy their growth. At about 3 inches high, begin fertilizing with quarter-strength high nitrogen fertilizer until about mid-May. At that point you can begin "hardening off" your begonias by exposing them to early morning sun outside. Remember that night time temperatures must be above 45 degrees before your begonias can be moved outside permanently for the summer. Once your plants have acclimated to the outdoors, switch to a bloom-producing fertilizer. Some upright plants may require staking because blooms can be quite heavy. Keep the soil evenly moist and when you think about it, mist the plants lightly. They will enjoy the extra humidity.

In the fall, when stems have fallen off the plant on their own, lift the tuber. Shake off dirt and dry the tuber in the sun for a day or two. Store the tubers in a cool, dry place, such as a garage. In March or April you can take them out and start again for the next season. You will have the satisfaction of raising tuberous begonias from "pups" as well as a summer of colorful bloom. Get them started NOW for summer enjoyment!

Q: I live in a rural area and it doesn't seem to matter what the weather, fire danger is always near. Do fire-tolerant plants exist?

A: There are not truly "fireproof" plant species, so plant choice, spacing and maintenance are critical to defensible space landscaping. Preliminary steps to protect homes from a future wildfire may mean the difference between property destruction and survival. Remove the "fuel" around your yard first, such as, weeds and dry brush. Reduce fuel by pruning shrubs and trees within your defensible space. Replace plants with fleshy-leafed plants that will smolder a lot longer before burning, since their foliage doesn't contain oils that make some brush explode in flames. Among more common ground covers are yellow ice plant (Delosperma nubigenum), stonecrop (Sedums, spp.) dead nettle (Lamium sp.) rockcress (Arabis sp.) These groundcovers can also reduce fire danger around tract homes. Deciduous plants also tend to be more fire resistant because of the moisture in their leaves, they have open, loose branches and they do not contain resin. Native plants similar to columbine (Aquilegia spp.), wild geranium (Geranium caespitosum) and dotted gayfeather (Liatris punctata) tend to be short and grow close to the ground and they resprout following fire, thus reducing relandscaping costs. Plant irregular small clusters rather than large masses. Break up the continuity of the vegetation with decorative rock, gravel or stepping-stones. Plant a variety of types and species and don't forget regular landscape maintenance. (See Fact Sheet #6.305 Fire Wise Plant Materials)

Q. I very much enjoy Mexican cooking, but have never grown tomatillos. Are tomatillos grown the same way as tomatoes?

A. Tomatillos (Physalis ixocarpa) are native to Mexico where they are known as tomate verde or green tomatoes. The tomatillo is a member of the tomato family and is similar in appearance. Similar to the tomatoes for the home garden, they prefer hot weather, warm soil, sufficient care and a seventy-day growing season. Tomatillos are referred to as husk tomatoes that must be peeled prior to using the fruit. Since the tomatillo is a hot weather crop, sow seeds indoors in cell trays, keeping seeds evenly moist, and use grow lights if available. Germination will take 7-14 days and they are ready for outdoor transplanting when the soil is warm and night temperatures are above 50 degrees. Transplant tomatillos when the seedlings are 3"-5" tall by burying them with soil so 1" of the seedling is visible. Water the base of the plant, not the foliage. Watering the foliage when the tomatillo fruit is maturing can cause the fruit to crack. Always mulch to retain moisture. The plants will grow to a height of 3 to 4 feet and mature in 70 days. Tomatillos are hardier and less prone to disease that the common garden tomato. Harvest when the fruit filling the husk is firm, bright green and has an acidic flavor. (See Fact sheet #7.605 Tomatoes for the home garden)

Q. My chives are out of control. They continue to produce non-stop and spread. I enjoy their texture and flavor in cooking. What shall I do?

A. You may wish to share the chives with a friend, but digging and dividing established clumps every few years is good for the plants. Cut the flower stalks to the ground after blooming and thin clumps every third spring. Space mature plants five inches apart. Sun-loving, extremely cold-hardy (Zone 3) perennials, chives ask only for regular water and reasonably fertile soil to be contented garden residents. Chives make an attractive border plant. The grassy texture of chive leaves also makes them a welcome addition to container plantings of herbs. As the growing season progresses, mulch will help the plants continue to flourish, especially those in containers. In very hot weather, the leaves may wither, but after a short rest, heat-stressed plants that are given regular water usually rebound and produce a new crop of tender leaves in the fall. The best-quality chive leaves are gathered in late spring. They lose their color and flavor when dried. These plants are appreciated as lovely perennials and die back to the ground when freezing weather comes but need no special protection to insure their winter survival. (See Fact Sheet #9.335 Growing, Preserving and Using Herbs, and Fact Sheet #7.614 Onions and related species.)

Boxelder bugs are all ready becoming a nuisance in some homes. Use a vacuum cleaner to control the bugs that are in the house. Laundry detergent mixed with water is a safe and effective "pesticide" but it has to be applied directly to the bugs to kill them. Household aerosol insecticides will also kill the bugs but again they have to make direct contact to be effective. The infestations should be over by late May as the bugs will have died or gone back to the host boxelder trees.

Fertilize spring blooming bulbs before their foliage withers. You can use a general fertilizer like 5-10-5 at a rate of 1/4 lb of N per 100 square feet. However, if you are overplanting the area with annuals the recommendation is 5 lbs of 5/10/5. Follow the recommendation on the fertilizer bag and water in well. Wash off any fertilizer that gets on the leaves.

Don't be in too big of a hurry to fertilize or prune your roses. It is better to wait until two weeks before the last frost (approx. May 10 -15 in Ft. Collins) so that new growth will not be damaged by a late freeze.

Turn your compost pile from last year and use the compost that is ready in your vegetable and flower beds. Save the debris you are cleaning up from the yard and garden to add to the green material you'll be putting in the compost later this summer. Soak the compost pile if it seems dry.

The authors have received training through Colorado State University Cooperative Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.

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This page updated:  May 3, 2004