April Stepping Stones

Weeks One and Two

Plan and Design

Continue to thin out perennials that multiplied or have out-grown their location. Transplant and practice 3D gardening (dig up, divide and deliver them to others). To lessen transplant shock, water the plants in good 24 – 48 hours prior to transplanting. Look over beds for plants that need to be hydro re-zoned into a different location.

Amend the Soil

Turn brand new beds one more time with a garden fork, or rent a heavy-duty tiller and mix things up (do not over till). Some improvement in soil texture should be apparent. If new beds were started in late fall, considerable improvement in soil texture should be noticeable. The microbes will have had close to 6 months to improve the soil quality. Let the soil settle and rest another two weeks before planting (or plant now if you did the final turn in mid March). Form any mounds and add the accent rocks.

Turf

Continue lawn prep for cool season turf of de-thatching (if necessary), aerating and feeding the soil by top dressing with both organic and inorganic amendments (insuring that the amendments have not been exposed to persistent synthetic chemicals; see Maintenance, Composting, Killer Compost). Mow with a mulching mower when necessary (cutting off no more than 1/3 of the leaf blade). If you don’t own a mulching mower, be sure to compost the clippings.

If the temperatures have averaged above 50º for awhile, warm season turf will begin growing grass blades. If the lawn has accumulated thatch (due to over fertilization and over watering), de-thatch now. Aerate turf and add soil amendments.

Take a look at the cool season turf. Is it thin with bare patches, or thick? A good thick, healthy turf keeps out weeds better than anything. If bare spots or just generally a thin grass cover is present, and if it wasn't re-seeded in March, do so now. With a hoe or rake, scratch down to the ground surface, an inch or so deep to loosen the soil, and add fine compost or worm castings. Broadcast the seed. Cover with a very fine layer (1/8th to not more than ¼ inch) of compost or worm castings to retain surface moisture better. Water gently and keep evenly moist with frequent, short intervals until germination and establishment. Before and immediately after germination, do not let these remedial or new turf areas dry out. As the seedlings develop a larger root system, gradually reduce the frequency of irrigation. If a strong, hard rain comes during this initial set up, the seeds may wash out.

Prepare the ground for any new warm season turf, if Bermuda grass or buffalo grass is your choice, rather than fescue.

Appropriate Plants

Watching the weather carefully, begin to plant cold hardy perennials. Avoid planting shock by hardening them off on the porch for 7 – 14 days to acclimate them to our outdoors, introducing them to sun gradually during the day. Bring them off the porch to an afternoon shaded location to break them gradually into full sun. They’ve been used to a nice cushy life in the greenhouse and need a period of adjustment, both to the weather, and to our sunlight. This technique is better than bringing them back into the house at night, where the degree of temperature span taxes the plant. It is safe to plant when the average minimum night temperatures (chill threshold) of the plant are reached. Harden plants off in temperatures above the chill threshold. The chill threshold varies for individual plants. The general rule of green thumb for gardeners is if it’s coming up, it’s safe to transplant. However, even though plants are hardened off properly, weather changes that drop temperatures below the chill threshold can be damaging.

As a new plant booster, I water in my new plants with organic microbial stimulators and/or fresh compost tea, in addition to planting with Yum-Yum mix in every plant hole. Keep a record of what's been planted where in your garden journal. I place the plant tag in back of the plant if it is a new, unfamiliar species.

Plant new cold-hardy summer blooming bulbs, such as the day lily, Asiatic lily, cannas, liatris, Kniphofia uvaria, the red hot poker, now.

Plant shrubs. If it’s a cool spring, plant your trees if you hadn’t already. This is the last period to plant trees until fall.

Spring Vegetables

Plant cool season vegetables now: lettuce, radishes, spinach, English peas, kohlrabies, cabbage, broccoli, and onions, etc. if already planted. This is the end of planting cool season vegetables until fall.

  • Onion seeds and sets may be planted from 4 – 10 weeks before the average date of the last frost (ADLF).
  • Lettuce and radishes can be planted 6 weeks before ADLF to 2 weeks after ADLF.
  • Irish potatoes should be planted 4 – 6 weeks before ADLF.
  • Sweet potatoes and English peas planted 2 – 8 weeks before ADLF.
  • Plant spinach, mache, kale, chard, bok choy, cilantro 1 – 8 weeks before ADLF.
  • Four to six weeks before ADLF is the time to plant asparagus, beets, broccoli, Brussel sprouts, cabbage, and carrots.
  • Two to six weeks before the ADLF is a good time to plant Swiss chard, collard, kohlrabi, parsley, turnip greens and roots.

Cover them with a sprinkling of mulch. Water them in and keep the ground moist. Don’t worry if they get snowed on; snow acts as insulation to keep the soil warm if a late blue norther blows through. Cover with a row cover or frost cloth. It's too warm to use a poly tunnel now until late fall/early winter. Row covers/frost cloths provide many benefits: decreases evaporation, keeps the ground warmer, keeps birds from eating the seeds and decreases wind damage. For new tender seedlings and plants, row covers are used to prevent sun scald.

Efficient Use of Water

Install new drip lines as needed. Check emitters, flush out the lines. Keep track of the ET rates and water when necessary.

Mulch beds and new plantings

Replenish beds if not already replenished and mulch new beds with up to 3 inches of organic mulch. Wood chips and bark are typical mulches. Composted cottonseed hulls, cocoa hulls, redwood or cedar mulch, composted leaf litter and grass clippings are some other typical mulches. Xeric beds normally will have inorganic mulch such as river stones or gravel. These will need replenishment periodically, as the stones and gravel work their way into the soil.

Maintenance

Apply corn gluten meal to cut down on weed seed germination (remember, do not use corn gluten meal in newly seeded vegetable and flower beds and turf).

Watch for aphids on roses and other forms of herbivory. Follow IPM practices in managing problems from the least harmful method on up.

Weeks Three and Four

Turf

Seed or re-seed warm season turf areas, following the similar guidelines as the cool season turf grasses. Warm season grasses best suited are buffalo grass and Bermuda grass. Both these grass genera have many different varieties that produce desirable turf. Two of the newest and highly rated buffalograsses are Turffalo®, and Legacy®. Warm season turf areas can be seeded, sprigged, plugged or sodded, depending on the variety. If you are faced with maximizing use of available water, lay sod. Someone else has already used the water to grow the turf sod to this size.

Appropriate Plants

Visit Canyon’s Edge Nursery for your native and adaptive plant needs. Make weekly trips to the other local nurseries and home improvement centers; their plant stock changes often. Remember to take your personal plant profile checklist with you to the nurseries. For gardeners, April and May are the best months of the year. Your gardening-impaired friends just don’t understand. Abandon your will to your voracious desire for new plants. Accept the fact that you’ve become a plantaholic. Acceptance of plantaholicism is the first step to becoming a great gardener. Enjoy life! Disclaimer: temper plant experimentation by consulting your plant profile. If the plant doesn’t fit the climate, soil, location, maintenance and your plan, keep looking. The pitfalls of plantaholicism is visual and olfactory inebriation of color and fragrance. Ask yourself, “once the bloom is off the rose, is this what I need”?

If the Panhandle nurseries don’t carry everything needed, this is a great time to head out of town. Go West, Gardener! Expand your plant exploration to Santa Fe Greenhouse or nurseries in Albuquerque. Or go south to Wichita Valley Nursery in Wichita Falls, or perhaps a favorite Lubbock nursery. While out of town, be sure to check out organic supplies and garden ornamentation too.

Some plants may still need to be hardened off before planting. Apply fresh compost tea or other organic stimulator and water in. Mulch the bed.

Plant non-cold hardy summer bulbs and tubers such as alliums, Amaryllis belladonna, the naked lady, Colocasias and Alocasias, (elephant ears), caladiums, cannas, dahlias and begonia tubers, gladiolus, oxalis, Zantedeschia, (the calla lilies), and Zephyranthes (rain lilies) after April 20th, or just wait until May. Planting these tubers in cold, soggy soil will cause them to rot.

Spring Vegetables

Plant warm season vegetables after the average date of the last frost (ADLF), April 20th.

  • Plant a final spring sowing of lettuce.
  • Plant 1 – 4 weeks after ADLF your beans, okra, pumpkin, and squash.
  • Plant cucumbers, cantaloupe, and mustard greens 1 to 6 weeks after ADLF.
  • Plant tomatoes 1 – 8 weeks after ADLF.

Efficient Use of Water

Check the drip system for watering effectiveness. Does the area the drip lines cover need to be increased because of plant growth? Drip systems installed for trees need to be increased (in area covered) to account for new growth.

Maintenance

Prune roses. Amend the rose bed with copious amounts of organic matter—they are heavy feeders. Watch for aphids every 2-3 days and spray them off with a stout jet of water.

Prune spring blooming shrubs if they require it and are finished blooming. Have a reason to prune. In the low maintenance landscape, gratuitous pruning is unnecessary.

Extra’s

  • Look over your garden with an eye for cosmetic improvements: improvements in hardscape such as garden benches, trellis’, new pots and containers, fountains and wall ornaments.
  • Set up the fountain if you already have one. I disconnect mine before winter.
  • Continue development of a new pond.
  • Plant warm season transplants towards the end of the month, or wait until May. Remember to harden them off to prevent plant shock and stress.
  • If you are thinking of planting fall blooming bulbs, April or May is the time to order them for best selection. Fall blooming bulbs haven’t caught on like spring bloomers, but if you’re a bulb enthusiast, order early for the best selection. Fall blooming bulbs include fall blooming crocus’, Crocus speciosus, C. pulchellus, C. medius, C. cartwrightianus, C. goulimyi, and the saffron crocus C. sativus, are some species to consider. Other fall blooming bulbs are the colchicums, specifically Colchicum autumnale, Lycoris squamigera, the surprise lily, and Zehyranthes (both summer and fall blooming varieties, not necessarily cold hardy).
  • Start looking for notices of home garden tours, or arrange one.

Be a Plant Explorer

Trips to botanic gardens, arboreta and conservatories really begins in April, when many plants begin to come in to bloom. For a complete listing of non-commercial institutions, go to www.nearctica.com, click on Table of Contents, then General Topics, then Organizations, then scroll down to Plant Related Institutions and choose your category. Browse and make plans.

View one of Texas’ greatest natural treasures, the stunning bluebonnet and other wildflower displays of South Central Texas. While you’re there, stop in at the Lady Bird Johnson Wildflower Research Center, in Austin. March is a little early to view the hundreds of native wildflowers in bloom. Many Texas native wildflowers will grow in the Panhandle.

Include a trip to the Rio Grande Botanic Garden and their Mediterranean and Desert Conservatory at the Albuquerque Biological Park while on a plant buying trip to Albuquerque or Santa Fe.

Keep It Up

  • Replant lettuce, radishes, etc. in two-week intervals to extend the harvest.
  • Keep weeding and mowing. Weeds seem to have the capacity to grow faster than our chosen plants, don’t let them get ahead and hog water and nutrients.
  • Continue to add plant debris to the compost pile and turn it every two weeks. Moisten it if necessary.
  • Continue to make daily/weekly entries to your garden journal. Record your precipitation and apply it to the ET rate for best use of our water resources.

Don’t or Oops!

If you’ve purchased impatiens, begonias, petunias, pelargoniums (geraniums) and other non-cold hardy annuals and perennials, wait until May to plant them. Nothing will be gained if a late frost or freeze rushes over us. Watch the temperatures and keep them protected. Don’t plant tomatoes until May, unless warmed and protected. Tomatoes and peppers hail from warmer climes and will quickly catch up if planted later.

Shimmering frost patterns on leaves by early morning light is beautiful, but to these warm season plants it can be damaging. Frost occurs when the dew point is below freezing and ice crystals begin to form on the exterior surface of a plant (freezing is ice that forms inside a plant and within plant cells). Tender, warm season plants, and hardy actively growing, but not acclimated plants are composed of soft, plaint cells that are easily damaged by frost crystals. Hardy plants that are acclimated are resilient to frost, but not necessarily to a freeze (The Weather Resilient Garden). Hardy perennials will often re-leaf, whereas the tender, warm-season annuals may be stunted or killed.

Do not buy and set out container annuals, especially tropicals in April. Plants in containers are more sensitive to environmental changes than plants rooted direct in the ground. Even nighttime temperatures in the low 50º’s are too low for tropicals. The minimum chill threshold for subtropicals is 33º – 40º. To be safe, this means the nighttime lows must be above 40 degrees for subtropicals, and 55 degrees for tropicals to safely leave them outside. The chill threshold varies from genus to genus, species to species, and variety to different variety. Even minimum exposures of 4 – 6 hours are enough for irreversible damage to occur in the cell membranes. These temperatures may damage their tissue and stunt their growth that will not be able to be overcome. Damage to the plant includes slowed and delayed growth, delayed or no flowering, blackened and death of leaves and reduced water and nutrient absorption. If you have subtropical and tropical plants, monitor the temperatures closely and plan to move then back and forth, inside and out.

Do not prune summer flowering shrubs until they’ve finished blooming.

Angie Hanna

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