This is an action-packed month for gardening. Gardens are bursting with color from all of the flowering bulbs and spring flowering trees and shrubs but you probably have weeds popping up everywhere as well. Temperatures are cool enough that its pleasant to work outdoors but its warm enough that perennials plants have broken their dormancy. This also is the month when we have our last frost making it a great time to plant annuals and vegetables. Following are some gardening ideas and suggestions to help you do the most for your garden this month:
- Shrubs and trees
- You can prune summer flowering shrubs like Crepe Myrtle after the last extremely cold weather but before they leaf out significantly.
- Prune spring flowering shrub like forsythia, weigela, Japanese quince, and lilac within 2 to 3 weeks after the last petals have dropped. Prune these shrubs at the base, near the ground to help rejuvenate its growth and keep it flowering heavy.
- Fertilize shrubs and trees if this wasn't done in February or March. Use an acid type fertilizer to feed evergreens, conifers, broad leaf evergreens, rhododendrons, azaleas and camellias. Use an all-purpose fertilizer to feed roses and other deciduous trees and shrubs. If you use granular type fertilizers, be sure to water it in thoroughly.
- Perennials, annuals, and bulbs
- Prune any semi-woody perennials like Salvia greggii, Lavender, Sage, Artemisia, and Careopteris.
- Prepare your annual planting beds now so they are ready when you want to plant. The addition of well-rotted manure, processed manure, peat moss or compost are good additives for building compost humus in the soil. I recommend not planting annuals until after April 15 th, our average last frost-free date.
- Plant tender bulbs and tubers (gladiola, lilies and dahlias). You may continue planting additional bulbs every two weeks until mid June to ensure a continuous source of bloom.
- Deadhead or remove spent flowers from spring blooming bulbs. Don’t remove foliage until it yellows or freely pulls loose when slightly tugged.
- Fertilize spring blooming bulbs just after blooming. A complete fertilizer such as 5-10-10 at a rate of 2 pounds per 100 sq. ft.
- If you noticed smaller blooms on your bulbs this spring, divide crowded planting as blooming finishes (especially daffodils).
- Watch for iris borer on your iris. For control, use Dimethoate (Cygon 2E) when the new growth is 6-9 inches in height and then as needed.
- Stake now, any perennials which lodge or fall over from the weight of their heavy blooms in late spring or summer. Staking now will allow plenty of time for new growth to hide your support structures, preventing them from taking away from the beauty of your perennials.
- Stake clematis and any other vines which could use the added support as new growth emerges and they begin to flower.
- Fruits and veggies
- While fruit trees are blooming, refrain from spraying any insecticides to protect the bee population busy pollinating the flowers. Within a week after petal drop, you can resume using any pesticides.
- After petal drop, consider spraying your peach, plum, and cherry fruit trees for protection from fungal diseases like brown rot, rust, and leaf spots. Maneb (also sold as mancozeb and dithane) works well for these diseases.
- You can still plant these cool-season veggies this month: spinach, head and leaf lettuce, collards, turnip greens, onions, beets, broccoli, cabbage, Brussel sprouts, cauliflower, carrots, early potatoes, radish and Swiss chard can be direct seeded or transplanted into the garden.
- After April 15 th, plant warm season veggies like tomatoes, peppers, and corn. Planting of the “high sugar” or sugar sweet corn varieties should b delayed until May 1 st because the seeds do not germinate in cold garden soils.
- Lawn care
- For warm season grasses such as zoysia or Bermuda grass, April 15 th marks your fist application of fertilizer. Use 1 pound of nitrogen per 1,000 sq. ft.
- Until April 15 th, its an ideal time to apply a combination of slow-release fertilizer and pre-emergent herbicide for crabgrass control to your cool-season (fescue) lawn. You want to apply this combination before dandelions reach the puff-ball stage. The fertilizer will boost the growth of your lawn and have it looking great for summer and the herbicide will prevent crabgrass. Numerous brands are on the market and which ever you select, be sure to follow label directions.
- Odds and ends
- Edge your garden beds.
- Clean your pond or water feature and remove winter debris. Cutback and remove all dead plant debris from your potted aquatic plants. Begin feeding fish around mid-April.
- Pull weeds now while the task is easy and the weather is pleasant. You may find it easier to use a chemical like Round-up to “spot” spray weeds in a flower bed. Be careful when using such chemicals to not spray it on desired plants. Round-up and its related chemicals are not selective herbicides and work by killing anything green.
- Its good to maintain a layer of 3"- 4" of mulch around your plants in your garden. Now is a great time to add any needed mulch to your garden getting it ready for the possibly hot and dry summer.