What to plant outside in April

$You can clean up all old vegetation left in a vegetable garden.  Just be careful not to walk on soil that is still very wet as you will compact it and make it much harder for plants to grow in later.  Make sure you remember what crops were planted in what areas last year, so you can rotate your crops this year. You can slowly and carefully remove mulch placed around plants to protect them as the weather warms.  Many gardeners leave it nearby to be quickly raked back over plants if a hard freeze threatens.  Be careful not to damage the growing shoots of plants as you rake beds.  If debris such as straw mulch, shredded bark or leaves isn’t too thick and matted it can just be left to decompose and add organic matter to the soil.  While this may look a little messy in early spring by the time we have a few warm rains and plants get growing it will disappear and be good for your soil.  Really thick mats of leaves or straw should be loosened or partially removed.Here’s a tip about mulches.  While mulch is great to keep plant roots and soil cool and moist in the summer, it also keeps soil cold and wet in the spring, when those conditions may not be ideal.  Rake back mulch from areas where you want to plant early crops to let the soil warm and dry out a bit.  And don’t add mulch to most beds until the soil has warmed a bit.  If the soil is dry, moisten it before adding mulch.  Letting the soil have some sun early in the spring may also help destroy some fungal disease spores and keep pests like slugs from getting a head start.All old dead annual flowers left in a garden can be removed.  Be a bit more careful and slower removing dead parts of perennial plants.  With plants that re-grow from the crown or roots each year such as hosta, daylilies, hibiscus, echinaceas and so on you can carefully remove dead plant parts left through the winter.  Be very cautious removing dead chrysanthemum foliage, the new shoots are at the base of the old and easily damaged.   Cut rather than pull off the dead foliage.   You can mow or burn off the dead blades of ornamental grasses.  (Be very careful with any fires in early spring as it is often dry enough to cause brush and field fires.)With woody perennial plants, plants that typically re-grow buds along old stems each spring, there may be some winter die back of the tips of stems.  Wait until the weather is warm enough that you can see the new green buds along the stems before you prune off what you suspect is dead wood.  Then prune the stems back to just a ½ inch above a green bud, so you don’t leave dead stubs.   Of course if you want the plant to be smaller this year you can prune it back to a ½ inch above any bud at the size you want it to be.  Any plant that has early spring blooms such as forsythia, redbud, flowering quince, lilac and so on should not have any pruning done until after the plant blooms, if you want spring bloom.Wait to prune evergreens, such as pine or spruce, until new growth has started.  Then do not prune past the last green bud on a branch.  Oaks should not be pruned after sap has started flowing, as this encourages a small beetle to spread a fungal disease that can kill them.  Fruit trees should be pruned before the buds swell also, but you can still trim off water spouts, thin branches that grow straight up along trunks and inner branches and any sprouts that pop up through the ground from the roots.If spring bulbs have bloomed remember that the foliage needs to be left until it dies down naturally if you want flowers again next year.  $
$April is a good time to plant grass seed in zones 4-6.  Grass likes cool, wet weather for germination.  Even a little snow won’t hurt it.  But do water it if spring is dry.  If piles of snow lingered a long time or puddles of water sat for many days you may have dead areas on the lawn which will need to be re-seeded.  If your lawn is up and growing mow it when it gets about 3 ½ inches long and only remove about a ½ to ¾ inch or a third of the grass blade at a time.  This keeps the grass green, healthy and dense.April is also a good month to fertilize lawns in zones 4-6.  Apply 3 pounds per 1,000 square feet of a high nitrogen fertilizer, generally labeled lawn fertilizer. (Nitrogen percentage is the first number on a fertilizer bag.) Follow the label directions.   Some fertilizers also contain weed killers or preventers, such as crabgrass preventers.  Lawn grub control tip.  Some fertilizers also contain grub or insect controls. Do not apple these products unless you know you have a grub problem.  However, in zones 4-6 grub control products containing imidacloprid, thiamethoxam,or halofenozide will not work to control grubs in the spring, regardless of what the bag says.   By the time summer comes when they would work, their effectiveness has greatly diminished if applied in April.  Apply these products in June or July for better results.  Products containing chorantraniliprole can be applied now but won’t work until later in the summer. Read the label to find out what ingredients are in the bag.If you feel you have a bad grub problem in early spring, because you can actually see grubs at the grass roots you can apply a product that has carbaryl ( Sevin) and/or trichlorfon as active ingredients.  They will reduce the grub population but aren’t as effective as applying the correct product in June and July. Michigan State University turf experts say that these products; lambda-cyhalothrin, gamma-cyhalothrin, bifenthrin, deltamethrin, cyfluthrin or permethrin do not kill grubs, although they may kill other insects on the soil surface.Remember that all pesticides can kill good as well as bad insects and other organisms such as earthworms.  They can also be harmful to children and pets. Don’t use pesticides unless you absolutely have to, and then use them only as directed on the label.  Don’t buy fertilizers with pesticides included “just in case.”  You’ll save money and the environment.$

Photo: USFS

What to plant outside in April

Any dormant plant can be planted as soon as the soil is thawed and not too wet as to compact when worked with or have standing water in a hole. A dormant plant is one that hasn’t got new leaves or big swollen buds yet. This includes trees, roses, strawberries, other fruit plants, and dormant bare root perennials. Most evergreens can be planted outside now too. For early color you can plant pansies and violas, which can stand frost and even a little snow. Most garden centers have them in April.

Perennial planting tip- when you go to a greenhouse or garden center in April you’ll find many perennial plants that are already growing, maybe even blooming. Because barely growing plants don’t have as much appeal to buyers the perennials are shipped in from the south or from a greenhouse. But if you take these plants which are weeks ahead in growth stages from plants in the ground and plant them outside in April in zones 4-7 the plants may experience shock, die back, or total loss.

Plant growing perennial plants outside when the same type of plants have begun growing outside in your area. For example plant that pretty new hosta outside when you see new leaves unfurling from your old hosta. The plants outside don’t need to be as developed as the potted plant but they do need to be actively growing. If you must buy perennial plants that are way ahead of plants growing outside in development, plan on protecting them with covers on cold frosty nights.

Remember when buying blooming perennials in early spring that they probably won’t be blooming at this time next year when planted outside. And if you are combining colors that look well together in the garden shop realize that they may not bloom in the garden at the same time when planted outside.

Most annuals and tender perennial bedding plants can’t be planted outside until after the last frost. (Coleus, impatiens, begonias, marigolds and so on.) That won’t happen until May at least for zone 4-7 gardeners. If you buy the plants now and try to keep them inside it will be a hassle and you will probably lose some. Garden shop owners know some people will buy them anyways, and then have to re-buy them later. Let the greenhouse care for them for a few more weeks and save your money.

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