The following "reminder list" is based on a Zone 6a growing region, which is centrally located for the North American growing areas. For areas north of Zone 6a add roughly one week per zone for any times given. For areas south, subtract roughly one week per zone. Don't know your hardiness zone? Find it quick on our "Plant Hardiness Zone Map".
 

May is the month when spring gardening starts to rock and many gardeners are at their busiest. The weather is warming and can go from one extreme to another in short order. In May, it is not unusual to go from warm days to frosty nights or severe storms that can destroy your hard work in short order if you aren't prepared.

May is the month when we put away the things of winter and replace them with the things of summer. The beautiful spring-flowering bulbs that renewed us in early spring are being replaced by spring-flowering annuals, perennials and flowering shrubs. The air is heady with the sights, sounds and smells of spring and many spring crops are at their peak. Thoughts start to turn to well deserved summer vacations and schools will be out for summer vacation, leaving children everywhere looking for things to occupy their time. What better time to get them actively involved in the garden and introduce them to the fascinating world of nature and instill in them skills, knowledge and interests that will be carried with them the rest of their lives?

Around The Garden

• When all frost danger has passed you can move your stored fuchsias and geraniums outdoors. Trim them back, feed and re-pot if necessary. Water them well.

• This is the month to plant corn, tomatoes, eggplant, beans, squash, cucumbers, sweet potatoes', etc. Keep an eye on the weather though, late spring frosts can still occur and you will need to protect your plants.

• Plants such as cucumbers, tomatoes, peas, vining beans and most squashes benefit from being grown on trellis and save ground space. Install trellis at the same time as you plant.

• Gourds may be planted late in the month. Grow on trellis for the best quality gourds and save space.

• Plant pumpkins by the end of this month to have ready for Halloween.

• Plant black-eyed peas when the soil warms to 65 degrees F.

• Remove spent flowers on spring flowering bulbs, but wait until foliage dies naturally before removing it. The remaining foliage is building food in the bulb for next years blooms.
• Old plantings of Daffodils may be divided and moved when they have finished blooming, but treat them as growing plants and use care to protect the foliage and roots. Water them thoroughly after transplanting. It is best not to dig or move other spring flowering bulbs until their foliage has ripened and died back.

• Dahlias, Gladiolas, tuberous Begonias, Lilies and Cannas and other summer flowering bulbs can be planted this month. Gladiolas bulbs may be planted at 2 week increments until the first of July to provide you with cut flowers until the first frost.

• Delphiniums, Phlox, Daylilies, Carnations, Aubrietia, Candytuft, Basket of Gold, Primroses, Coral Bells and Saxifrage and other summer flowering perennials may all be set into the garden any time in May.
• Pansies, Snapdragons, Dianthus, Petunias, Geraniums, Fuchsias and Impatiens should be ready to plant by mid month. Toward the end of the month, it should be warm enough to plant out the more tender annuals like Salvia, Zinnias, Marigolds, Lobelia.
• Lightly side dress perennials with an all-purpose 5-10-10 or 10-10-10 fertilizer. Avoid spilling the fertilizer on the plant, and use care not to damage the shallow roots when you cultivate it into the soil. Water well.
• Remove spent flowers of peonies, but do not remove leaves until fall.

• Promptly remove spent flowers from any plant unless your intent is to harvest the seeds. It consumes the plants energy to produce the seeds, and in many species of plants (especially annuals), removing the dead flowers will promote further blooms.

• Begin pinching top 1-2 inches of new growth on chrysanthemums to encourage full bushy plants. Stop pinching in early July.
• With clump-forming perennial flowers such as asters, monarda, and tall phlox pinch out the top growth of the front half of the clump. This technique extends the bloom time since the front half will bloom about 2 weeks later and also shapes the clump into cultured tiers.
• Experiment with pinching back the top growth of tall sedum to keep it from flopping apart. Smaller flowers will arrive later, but will be more numerous. If the plants are getting plenty of sun, this may be a good alternative to staking.
• Set flower supports early. Let plants grow through them.

• Get watering equipment ready and put in place this month for the warm, dry weather ahead. Soaker hoses work best when installed under the mulch you will be applying later.

• If the weather is sunny and dry, don't neglect your watering. Most vegetables, flowers and shrubs need about an inch of water each week to perform well, and newly planted seedlings will perish if their roots are allowed to dry out.

• Thin carrots and beets to allow root development.

• Continue to harvest asparagus and rhubarb.
• Prune sage, rosemary, bay, lavender and other herbs to stimulate new growth.
• Plant transplants or seeds of annual herbs such as basil and dill. Sow extra dill or parsley for the swallowtail caterpillars.
• Do not irrigate late in afternoon. Foliage should be dry at night to help prevent diseases.
• Be sure to read, understand, and follow all pesticide label directions.

• Your compost pile should be in huge demand this month with fresh compost coming out and new material going in. Don't neglect to turn it completely and keep it damp so that it will continue to work as hard as you are.

• Start harvesting herbs for drying this month. Hang bunches of herbs in small bundles up to dry for later use. Secure stems with a rubber band to keep them tight as they dry. Hang upside down in a warm, dry location until thoroughly dry.

• Turn your compost pile to keep it working and cover it during times of rainy weather to prevent leaching.

Around The Landscape

• Plant tropical water lilies when water temperature is over 55º F.

• Get sprinkler systems working and check for proper operation. Make adjustments as necessary to make sure that only the grass is watered. Don't waste water on streets, sidewalks, etc. Check for any obstructions in watering patterns such as trees, low-hanging limbs, etc.

• Work lime in the soil around your Hydrangeas to produce pink flowers or Aluminum Sulphate for blue.

• Severely prune butterfly bush, Russian sage, and Caryopteris to stimulate growth.
• Fertilize lawns in early May with one pound of actual nitrogen per 1,000 square feet. Slow release nitrogen forms are preferred and water well.
• Apply moss killers before temperatures reach 65 degrees.
• Grubs are active now, both in your lawn and gardens. Start applying repellents and other controls this month.

• May is a good month to repair your lawn. Fill in the bare spots by slightly loosening surface of the soil and sow a good quality lawn seed over the area evenly. Tamp the seed in gently and water. Keep the patch moist by covering with light mulch of lawn clippings or straw.

• Setting your mower for a higher cut during the spring months will help the grass to grow in fuller and help choke out the weeds.
• Continue post-emergence herbicide treatment or hand pulling for broadleaf weeds if necessary. Don't let them go to seed!
• Continue control of insects and diseases on fruit trees.

• Remove any sucker growths from fruit trees as soon as they appear.

• Lilacs should be pruned lightly after they finish blooming, removing sucker growths and dead blooms.. Feed lilacs in May with a good all purpose 10-10-10 fertilizer after they have finished blooming. If your soil has an acidic pH, work a little lime into the soil as well.
• Pinch azalea and rhododendron blossoms as they fade so that the plants energy can go to foliage growth and next years flowers, rather than seeds.

• It's still not too late to fertilize your trees and shrubs. Use a 'Rhododendron' or an 'Evergreen' type of plant food to feed evergreens and acid loving plants like Rhododendrons, Camellias, Azaleas, and Junipers, etc. Use an all-purpose garden fertilizer (10-10-10) to feed roses, deciduous shrubs and trees. Be sure to water the fertilizer in thoroughly after it is applied.

• Fertilize flowering shrubs like Rhododendrons, Camellias and Azaleas immediately after they have finished flowering with a 'Rhododendron' or 'Evergreen' type fertilizer.
• Dead head the developing seed pods from your Rhododendrons and Azaleas to improve next years bloom. Be careful not to damage next years buds which may be hidden just below the pod.
• Prune spring flowering shrubs such as lilac, weigela, viburnum, and flowering almond soon after bloom using renewal method. Prune oldest stems to the ground to encourage better flowering. Early flowering deciduous shrubs such as Forsythias, Weige and Spiraea should be pruned back when they have finished blooming. Cut back a third of the oldest canes to ground level, then cut back one third of the remaining branches by one third of their height.

• Pines and other conifers can be kept to a compact size by pinching off the new growth 'candles'.

• Monitor pines especially Scotch and mugho for caterpillar-like sawfly larvae on new shoots. Hand removal is effective or insecticide sprays of spinosad, neem oil or carbaryl.
• Late May scout for pine needle scale and oystershell scale crawlers by circling stems with inverted black tape. Young crawlers are present about the time bridal wreath spirea is in late bloom or has finished bloom. Timing is crucial for scale control. Insecticidal soaps and summer oil sprays are effective.
• Practice good sanitation. Remove and destroy diseased leaves. Disinfect pruners, knives, etc. between cuts with a solution of one part chlorine bleach to nine parts water to prevent contamination of non-infected plants.

• Keep a vigilante eye on the roses. Keep them sprayed for aphids and other pests and diseases such as black spot.

• Remove all yellowed and black-spotted foliage (burn or place in trash). Spray every 7 to 10 days with fungicide.
• Slugs and snails are out in full force right now. Be sure to take steps to control them now, before they have a chance to reproduce and devastate your garden.

• Fertilize your roses every four to six weeks with a slow-release fertilizer and water well. Discontinue fertilizing by mid August.

On The Patio

• You should be starting to use your patio regularly this month and you should consider incorporating pots and planters wherever you can to soften lines and create that special ambiance.

• If pots and planters enjoy a place on your patio, place spacers under them to allow air movement under the containers. This will reduce or eliminate stains on your patio or deck.

• If you use chemical fertilizers in your containers, place trays or saucers under them to catch the water that drains out. this will reduce stains on your patio.

In The Shed

• The garden shed will see a lot of activity this month. Make a renewed effort to put everything back where it belongs to reduce clutter later.

• Much of your work may run into the evening hours. It's very frustrating to grope around in the dark to return tools, etc. Consider adding some lights to your garden shed. If you can't add electricity, consider adding a kerosene or battery powered lantern or two. These can be an inexpensive, valuable and useful asset after dark.

• Consider a solar power system as an alternative to running a conventional power system for your garden shed. Systems are available that will power a light or two and often an additional plug so you can play your favorite tunes while working or a drill, etc. and often for less than what it may cost for a conventional power system.

In The Home

• Over-wintered tender annuals or tropical's such as hibiscus, gardenia, mandevilla, and geranium may be pruned, cleaned, and fertilized. Gradually move to protected location outdoors.

• Gradually move your houseplants outdoors to enjoy the summer outside. Set them outside in a shady location for a couple of hours then bring back indoors. Increase the amount of time outdoors each couple of days until they are acclimated in a week or two. Remember they will require more water outdoors than in and outdoor light is more intense than indoor light. So most plants that enjoyed a sunny windowsill indoors will need some protection from direct sunlight outdoors, especially during the bright sun of midday.

• Check to see if your house plants are rootbound. Water them thoroughly and carefully remove them from their pots. If the roots have compacted around the outside of the rootball, it is time to repot.

• Carefully examine your houseplants for pests and problems. It is much easier to fight an insect infestation or disease in it's early stages than to wait....
• As the growth rate of your house plants increases with the seasons, adjust your feeding schedule to provide additional food. Feed your plants a good all purpose house plant food at half of the manufacturers recommended rates, increasing the proportion slightly to accommodate growth spurts. Overuse of fertilizers can cause root and foliage burn, as well as the death of the plant.
• Mist your plants regularly. This adds to the humidity, keeps the leaves cleaner and healthier, and helps to prevent spider mites.

For Yourself
 

• May can be a month of weather extremes. Protect yourself and loved ones by purchasing a weather alert radio and stay informed on weather forecasts.

• May is also a time of gardening inspirations and dreams. Look around yourself and notice what your neighbors are growing in their gardens and what they are creating in their landscapes. Think of how you might utilize some of their ideas along with your own brainstorms to make your garden just a little bit better.

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The information presented in a gardeners calendar is derived from many sources including practical experience of the writer. While we strive to present only fact5ual information, no guarantee is given, whether expressed or implied as to its completeness or accuracy. PO'Folks Ozark Mountain Enterprises accepts no responsibility for any damages resulting from the use of this material. As with all things, PO'Folks Ozark Mountain Enterprises urges all readers to exercise sound reasoning before applying any information they may obtain from any source.