Al Krismer Plant Farm presents ........

April 2018  GARDEN TIPS

  Tips  for a more beautiful garden


 Perennials, Annuals, and Bulbs:
  • If your houseplants or any seedlings you may have started are becoming leggy, Thatís a classic sign that they are not getting enough light. Suspend a simple fluorescent shop light 6-8 inches above the leaves or your plants.
  • Start seeds of warm-season plants, including tomatoes, peppers, eggplant, marigolds, zinnias and petunias, indoors for transplanting later to the garden
  • Resist the urge to plant during warm spring weather. Temperatures can vary widely from day to day in the spring. It is not unusual to have a few days in the 70ís followed by cold 40 F temperatures. Our average date of last frost is around May 15, but you should always be prepared to cover newly planted plants during spells of cold weather.
  • If cold frosty nights should bother your plants, never use plastic sheets as a frost protector. Use either cloth sheets or newspaper. Try if possible to prevent any of the covering touching the plants.
  • Its not a good idea to try to protect exposed and opened blooms of daffodils, tulips. or hyacinths from the cold since the weight of the covers will damage the flowers. Opened flowers can withstand a few degrees of frost, while buds should be able to cope with 20 degree temperatures.
  • Control iris borer by cleaning up and destroying the old foliage before new growth appears
  • Remove mulch from roses and perennial flowers if they begin to sprout.
  • Ornamental grasses: Cut down the old, dead grass from all of your ornamental grasses. Use hedging shears.
  • Harden off summer bedding plants. They must be slowly aclimatized to outside conditions. Do not place outside if there is risk of frost.
  • Caladiums and Tuberous Rooted Begonias can be started indoors in pots of moist sphagnum peat and soil mix; then plant them outdoors in May. Make sure soil temperatures are kept above 60 degrees.
  • When chrysanthemums show signs of life, dig up and divide large plants. Discard woody portions and replant divisions 12 to 15 inches apart

    Harden off transplants started earlier in spring before planting outdoors gradually expose the young plants to outdoor conditions of wind, brighter sunlight and lower moisture.

Vegetables and Herbs

  • Sow seeds outdoors for the following crops: beets, carrots, chard, kohlrabi, leaf lettuce, mustard, onion sets, parsnips, peas, potatoes, radish, spinach and turnip

  • Rotate vegetable crops to help control pests, disease and to keep the soil in good condition.

  • Herbs that can be planted this month include parsley, thyme, rosemary, sage, mint, oregano, tarragon and dill. Wait until May to plant basil; it won't do well until the soil has warmed up and night temperatures are consistently warmer.

  • Put small felt collars around young cabbage plants to protect the roots from being attacked by root flies.


For soil testing info click here

Garden Maintenance:

  • Prepare your garden soil for planting. Dig or till the soil at least 8-12 inches deep. Do not dig soil when it is wet. Soil tilled when wet will dry into clods of concrete. Check soil before digging by squeezing a handful in your hand. If it crumbles easily between your fingers, go ahead and dig, but if it stays in a ball, allow the soil to dry an additional couple of days
  • Look for termites, carpenter ants, and box elder bugs which emerge on warm days. Check for cankerworm masses on maples, oaks and flowering fruit trees. Look for eggs masses of tent caterpillar , gypsy moth and bagworm on trees and shrubs. Be sure to remove and destroy any you find.
  • Get your containers ready for planting next month. Salt-encrusted clay pots can be soaked in a solution of 10 parts water to one part chlorine bleach for about a week to remove the salt and disinfect from diseases. Scrub pots and hanging baskets and stock up on potting mix (choose a blend of perlite, vermiculite, and peat moss) in preparation of planting containers
  • Watch out for tent caterpillars in cherries, crabapples and plums. When the caterpillars are small (less than 1" long), you can spray with an organic product such as Thuricide or BT. These products are only toxic to caterpillars. If you wait until the caterpillars are longer than 1", however, you will need to spray with Sevin.

  • Fertilize woody plants before new growth begins. Two pounds of actual nitrogen per 1,000 square feet should be sufficient
  • Plant or transplant asparagus and rhubarb crowns. For best plant establishment, do not harvest until the third year after planting
  • Check the brackets used for hanging baskets. Once the flowers are in full bloom and compost is moist they will become much heavier.

Shrubs and Trees:

  • Spring is pruning time. Correct pruning of spring flowering shrubs will provide more blooms and keep the plant healthy. Lilacs, forsythia and spireas should be pruned two weeks after blooming. Shrubs that bloom in the spring need all summer to produce flower buds for next year
  • Late March and early April is a ideal time to transplant shrubs and trees. You can move shrubs and trees as soon as the soil is workable, but before buds have swelled or broken open.
  • Check upright junipers and red cedars for the brown galls of cedar-hawthorn/apple rust. They will be mingled with the leaves and resemble brown golf balls. Warm spring rains cause them to ooze orange gelatinous "horns" which spread spores to apple, crabapple and hawthorn. Remove these galls before they erupt to limit the spread of spores
  • Plant and transplant trees and shrubs as soon as the soil is dry enough to be worked. Bare root specimens should be planted before they break dormancy; balled-and-burlapped and containerized stock can be planted anytime during the growing season. After planting don't forget to water well and mulch!
  • Prune evergreens (except pines). Keep the pruning cuts within the green (foliage) parts of the plant. If cutting goes back into bare branches it is sometimes difficult or impossible for the plant to re-grow from the old growth
  • Pines will produce new candle growth from terminal buds later this spring. In some cases, a pine that looks brown now may look much better when the new growth emerges. Take a wait and see approach with pines; do not prune them now, as the terminal buds will be removed and no new growth will occur on that branch.
  • Azaleas will be blooming this month. Remember not to fertilize azaleas until after they have finished blooming
  • The last Friday in April is National Arbor Day. Plant a tree, or support an organization which does.
  • Don't forget to water plants under overhangs. Water new plantings and blooming rhododendron regularly. Feed Rhododendron right after they bloom. Nitrogen is required but not available naturally
  • Time to plant fruit trees and grapes. Some fruit trees need a pollinator (two different kinds that bloom at the same time).

Lawn Care:



  • Prepare lawn for the mowing season. Rake away all twigs and debris. Have the lawn mower blades sharpened, replace the spark plugs and change the oil.
  • Nowís the time to get the mower out of the shed, make sure it starts and is ready to go when you need it in the next few weeks. Be sure to sharpen the blade and make sure the mower is working well mechanically. You should begin mowing at 3 inches or so once the grass plants start to grow and reach about 3.5 or 4.0 inches tall. This normally happens well before most of us start mowing because we see mostly brown leaf blades and we donít think the lawn is growing. However, grass plants grow from the bottom up where the new green leaf material elongates near the soil, pushing the older brown leaf material up into view. The first mowing generally will remove almost all of the old brown leaves revealing a nice green lawn below. Though none of us want to do it, itís better to start mowing your lawn too early than too late.
  • Prevent crabgrass and other grassy weeds before they start by applying a pre-emergent herbicide before the ground temperature reaches 55įF (i.e., before the yellow forsythia stops blooming and before the lilacs blossom). Crabgrass is an annual weed that re-seeds itself each year. It is difficult to control once it is up and growing, but a pre-emergent herbicide will kill the seed as it germinates. If you plan to reseed bare areas in your lawn, use a pre-emergent specifically labeled for new lawn establishment.
  • Avoid applying nitrogen-based fertilizers when your lawn is dormant and has not greened-up; the growing stimulant provided by the nitrogen could end up encouraging the growth of broadleaf weeds or other unwanted grasses in your lawn. Allow the grass to green up, grow, and be mowed once or twice before applying fertilizer in late April or early May
  • You may have grubs if there are lots of birds feeding on the ground in your yard; if you have patches of brown grass that pull up easily; or if you've spent the time and energy to dig down a foot and have found adult grubs.
  • Repair bare spots in the lawn. Work up the soil well in these areas incorporating some granular fertilizer, too. Sprinkle on a good seed mix of bluegrass and fescue. Rake lightly to mix seed with soil. Tamp to assure seed-soil contact. Mulch lightly with straw. Keep well watered for two weeks until all the seed has germinated

House Plants:

  • A popular gift plant, the Easter lily, needs bright, indirect light. Avoid direct sunlight and keep the soil moist. After blooming, it can be planted in a sunny spot in the garden after danger of frost is over, where it will bloom next year
  • Longer days and higher light intensity means indoor plants will begin growing faster. Start fertilizing again using a half strength solution every other watering. Prune hard now to stimulate new, bushier growth.
  • Repot houseplants. Repot your houseplants when roots grow through the drainage holes, when the soil mass is filled with roots, when new leaves are smaller than usual or when the plant wilts between waterings


Spring Pond Care:

  • Remove leaves and debris from ponds.

  • Inspect The Pond Take a careful look around your pond. Make sure there has been no winter damage to the pond or any of the components. Repair or replace as necessary.

  • Start Pump If your pump has been off for the winter, spring is the time to start it back up. Most people do this when the water temperature increases to around 50 degrees.

  • Test Water Begin testing the pond water again. Of particular importance are ammonia and nitrite levels. Both of these should be zero. Perform partial water changes if either test gives a reading other than zero.

  • Warm weather means your fish are now or soon will be ready to start eating again. Until the water temperature is consistently above 50 degrees, continue to not feed the fish. Once the water temperature is into the 50s you will want to feed a food designed for spring and fall. As the water temperature reaches into the 60s it will be time to feed your regular summertime fish food.

  • Also as the water temperature reaches into the 50s it will be time to get the hardy plants that survived the winter ready for a great year ahead. This is the time we begin fertilizing the plants. Also, for maximum performance, it may be necessary to divide some of these plants. If the plants are too crowded in their pots, they will suffer and their growth and flowering potential limited.

  • If you have a backyard garden pool, now is the time to clean it and refill it with fresh water. You can plant hardy water lilies from now until May.


Birds in the Garden

  • Put out the hummingbird feeder towards the end of the month. Use a 1:3 ratio of sugar to water (ex. 1 cup of sugar to 3 cups of water). Boil for 3 minutes. Cool and serve. Some say to switch to a 1:4 ratio after the first couple of feedings

  • Birds will be ready to start nesting this month so if you want them in your yard you will need to have your bird houses cleaned of last yearís nests and placed out in the yard. Check your dryer vents as it is a tempting place to put a nest. Cover your chimney to prevent birds, bats, squirrels and even raccoons from nesting in your house.


  • Place birdhouses built this winter outdoors this month. Birds will begin looking for nesting sites soon


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